DE2656028A1 - LIGHT PROBE - Google Patents

Description

Licht.son.de

The invention relates to a light probe or the like for point-like and general lighting of an optically sample to be checked or an object, for example a tooth in the mouth of a patient / wherein the ambient lighting influences are simulated and a liquid boundary or intermediate layer the optical coupling properties of the light probe or the like improved »This is a further development of an object according to the US patent application 499 491 of August 22, 1974, which relates to a boundary or intermediate layer for light probes.

The present invention provides for a reduction and / or elimination of undesired specular light reflection from a sample subjected to optical inspection. Such optical testing or checking can take the form of coloring, Occupancy or density, opacity or opacity or the like measurements are carried out, and the invention will be described in detail below in connection with a tristimulus-type colorimeter as described in the above U.S. patent application is disclosed dealing with a tristimulus colorimeter and a method of using the same for making artificial teeth or the like. The following description is to be regarded as merely exemplary, and it is clear that in reality the invention can be used with any optical test or test. Test instrument or light probe device can be used to establish the optical coupling between a light conducting member and to improve the specular reflection properties of a sample of a shiny sample and / or to form a point-like and general illumination of a sample.

The prior art includes numerous types of light-conducting members, such as solid or solid or hollow non-conducting rods, Fiber optic bundles and the like, for guiding incident light to a sample and / or for receiving light that

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was reflected from a sample. In the present description, the word 'sample ¹ ' refers to a structure to be optically checked, which may be an unknown object, a reference object with known optical properties or the like.

A disadvantage of many known optical inspection devices, in which light-conducting members are used, the undesirable specular light reflection is at the interface between the limb and a relatively clear, shiny surface of a specimen, such as a tooth, with a sufficient color, Turbidity or the like property. In addition, at an imprecise boundary point between a directly adjacent light-guiding member and a sample undesired light refraction and / or scattering occur, whereby inaccuracies can result in the optical measurements of the sample. Such an unclean or incomplete interface can in particular then arise when the essentially smooth or flat solid end or the tip of a light probe on the relatively corrugated Surface of a tooth is brought to bear. While by holding one exactly at right angles to the sample Light probe creates an optimal optical coupling, it can happen that different operators or technicians Hold the light probe at different angles relative to the sample and therefore obtain different measurements of the sample.

It is desirable that the stain or similar tooth measurements take the Reproduce the color of each tooth as it would naturally be seen by an observer under typical ambient lighting influences sen is seen. In order to make such measurements, the illuminating light must usually have an intensity greater than is that of typical ambient light. For example, if the tooth color is for a subsequent renewal by a When measuring an artificial tooth, the size of each test point checked on the tooth should be a small area, so that many measurements, for example nine or more, can be taken to establish a color gradient for the tooth. However, when measuring such small test point ranges,

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before a source of error adjust, for example as a result of the non-uniform Transparency of the teeth, which can result in different amounts of the illuminating the respective points incident light are scattered away by a light probe holder, which adversely affects the measurement accuracy will.

A main object of the present invention is to improve the accuracy of the optical measurements. The specular reflection at the interface between a light probe and a Sample should be reduced and / or eliminated. Furthermore, a liquid extension of a solid light guide is to be created will. Deviations in the optical measurements should also be avoided, for example due to misalignment between the light probe and the sample are justified. The scattering and refraction at the interface of a light probe and a Sample should be reduced and / or switched off. Natural lighting influences should also be optically checked on one Tooth or another sample can be simulated. And finally, a removable translucent end cap for a light probe system is intended be created.

To achieve the object set, a light probe of the type mentioned is characterized according to the invention by a liquid-like one Interface means between at least a part of the solid end face and the sample for optical coupling these parts in the places where they do not directly abut one another. According to the present invention, the solid or solid end part a light-guiding member that guides light to a sample to be optically checked and / or reflected from it Receives light, with a lot of clear, viscous or thick, translucent, liquid or liquid-like Material provided, such as glycerine or the like, this material having a refractive index of about the same size as the Limb and the sample has. The liquid boundary layer improves the optical coupling between the light-conducting member and the Sample, even if one or both of the latter parts are inaccurately

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are shaped and, for example, have a slightly wavy surface like a tooth. The same applies if these parts are not exactly, that is, not at right angles / aligned. Despite these inaccuracies, optical measurements are accurate according to the invention the sample possible.

In addition, according to the present invention, the influences an ambient lighting when illuminating or irradiating the sample is simulated. In detail, the limited test point or -area of a sample to be visually checked with primary, uniformly incident light via a specific, direct light conduction path, which is the solid end of a Includes light probe. Furthermore, a secondary illumination is used in a ring area extending around the test point or area the rehearsal taken care of. The intensity of the incident secondary lighting corresponds to an area that is directly related to adjoins and surrounds the test point, the intensity of the primary illumination of the test point, and the intensity of the secondary Illumination can remain uniform in a direction radially from the test point or can be relatively stepped or gradually decrease.

Furthermore, the light probe according to the present invention is with an end cap provided for sterilization after an application is removable on a dental patient and for subsequent use on another patient. The removability may also serve the purpose of discarding the end cap after one use and another similar sterile end cap to replace. The end cap contains the light probe tip for primary lighting and an outlet of a light conducting path for secondary lighting. Can also be a liquid boundary or intermediate layer between the end cap and the light-guiding main part of the light probe are used, to improve the optical coupling between these parts.

According to the invention, therefore, a relatively viscous, translucent one sits liquid material, such as glycerine or the like, on the solid

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End part of a light-conducting member to the optical coupling on a sample to be optically checked or an object with an irregular and / or shiny surface. In addition, the light probe system has a test end with a tip that is largely on a test or test area or Test point of a sample is brought to the facility. The tip provides a point or primary illumination of the test point, another Source provides general or secondary illumination of the sample in an annular area around the sample tip as well as the test point, so that when the sample is illuminated Ambient light influences can be simulated.

These and other objects, features and advantages of the invention emerge from the following description of graphically illustrated embodiments that are only exemplary in nature and include some of various embodiments of the present invention. Show it:

FIG. 1 - in a partially sectioned side view, a light probe coupled to a tristimulus colorimeter and a boundary or intermediate layer according to the present invention,
Figure 2 - a top view of a color filter wheel of the colorimeter from Figure 1,

FIG. 3 - in an enlarged, partially sectioned partial side view the test end of the light probe and the liquid boundary layer according to the present invention in Operating position on a translucent sample,

Figure 4 - in a graphical representation, the intensity of the incident Light over the surface of the sample from Figure 3 and

FIG. 5 - in a partially sectioned side view, another Embodiment of the light probe according to the invention.

Similar reference numbers indicate corresponding parts throughout the several figures of the drawings. According to Figures 1, 2 and 3 contains a light probe instrument or device according to the invention, generally designated by the reference number 1, a longitudinally

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ches main light guide part 2. The light probe 1 is at its test or. 4 testing end with a lot of permeable, liquid-like Provided boundary or intermediate layer material 3 and coupled at its other end 5 to a tristimulus colorimeter 6, that is in more detail in the aforementioned U.S. Patent Application No. 499,479 is described. It should be noted, however, that the light probe and the liquid boundary layer according to the present invention Invention in connection with the colorimeter 6 deviating optical measuring systems can be used, as it is from the present description.

The part 2 of the light probe 1 contains a pair of light-conducting members 7 and 8, the former being a conductor for incident light for illuminating a sample 9 shown in Figure 3 and the latter member as a conductor for light reflected from the sample back to the colorimeter 6 is used to measure the same. Both limbs can be used for protection and for Avoid environmental influences by means of a conventional plastic or rubber cover or shell. Preferably, the two light-conducting members 7, 8 are cylindrical and the former has a hollow area, in the one length of the latter link from the usual transition 1o extending to the flat end surface 11 at the test end 4 is arranged concentrically. Thus, a bifurcated light guide device is formed that is solid, hollow, fibrous, or the like can be formed. Part 2 is also the test probe preferably relatively flexible in order to more easily bring the test end to bear on a sample 9, such as on a tooth in the mouth of one dental patient.

For manual detection of the light probe 1, the concentric light-conducting members 7, 8 at the test end 4 are of a metal or Plastic housing cover 12 that is easily cleaned or surrounded can be sterilized. A arranged over the cover end cap 13 abuts with a flat surface 14 substantially the flat end face 11 of the light conducting members 7, 8. The end cap 13 has a holder with a cylindrical holding part or collar 15 which engages over the cover 12, and a relative

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flat, ring-shaped, translucent disk 16 which holds a cylindrical, relatively long light probe tip 17. The latter
has a fixed end surface 18 which is brought into contact with the sample 9, as shown in FIG. The light probe tip 17 can, as shown, in a bore in the disk

16 be set, but it is also possible to use the tip
and to form the disk in one piece. At least the tip and the disc of the end cap 13 are translucent and consist
for example made of clear plastic, glass or the like. Furthermore, the tip 17 is preferably internally reflective in order to make the primarily incident light diffuse and to ensure that the light reflected by the sample 9 and received at the fixed end face is not transmitted through the elongated surface and to the environment is enough. Therefore, a light reflective coating 19 can be provided on the elongated outer surface of the light probe tip for this purpose

17 running from the surface 2o of the disk to the fixed end surface 18 be provided.

When the end cap 13 is arranged over the end of the light probe, the longitudinal axis of the light probe tip 17 preferably coincides
the common longitudinal axis of the light-guiding members 7, 8 together, and the diameter and cross-sectional area of the light probe tip 17 are on the abutting surfaces 11,
14 larger than the diameter and cross-sectional area of the
light-guiding member 8. Therefore, light incident from the colorimeter 6 can be transmitted through the outer light-guiding member 7. Part of the incident light passes from the light-conducting member into the light probe tip 17 in order to provide the main lighting for the test point or area 21 of the optically checked
Tooth 9 to form. The optical properties of the preferably
transparent light probe tip 17 ensure that the through
Solid arrows 22 denote main lighting or exposure over the entire surface area of the test point 21
is substantially uniform. Of the main exposure 22 impinging on the tooth 9, a part, shown schematically by dashed arrows 23, is reflected by the tooth and by

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the light probe tip 17 was added. This reflected light 23, which is a coloring or other optical information of the tooth 9 contains, is guided by the light probe tip back to the facing surfaces 11, 14, where part of the reflected Light enters the light guiding member 8 to be guided to the measuring part of the colorimeter 6.

However, another part of the incident main light 22 tends to in the tooth 9 from the test point 21 repellent scattered or completely to be transmitted through the tooth. In any case, this part of the incident main light is not in the sense of a recording reflected by the light probe tip 17. In addition, the part of the main light incident on them changes Way in which tooth 9 is lost, from one checkpoint 21 to another depending on the respective light transmission of the tooth at each test point. This can result in the The degree of inaccuracy of the color measurement is different for each test point in the entire surface area of the tooth. If further the tooth is irradiated with secondary light, which is shown in FIG the dashed lines 24 shown, such inaccuracies noticeable, reduced or switched off. This result can be achieved by adjusting the intensity of the main exposure 22 and the intensity of the secondary irradiation 24 reached immediately outside the probe tip adjoining the test point 21 will. If the secondary intensity is essentially uniform, i.e. does not vary greatly, ambient exposure effects can occur can be simulated, reducing the amount of light scattering into and out of the field of view of the solid or massive End face 18 of the light probe tip 17 are largely aligned. The secondary exposure 24 also exits the light-conducting member 7 and passes from there through the transparent disk 16 of the end cap 13 and the surrounding Air to the tooth. A part of the secondary irradiation light 24 denoted by a dashed arrow 25 in FIG. 3 becomes back to the test point 21 and thus reflected into the light probe tip 17, to be recorded by this and used for the subsequent measurement by means of the colorimeter 6.

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Since the secondary exposure 24 after leaving the light-guiding Member 7 is not restricted, the intensity with respect to the actually illuminated test point 21 changes accordingly the inverse or reciprocal law of the square. Around the test point 21 under substantially uniform lighting conditions check that simulate the effects of ambient lighting so that the tooth is as natural to the colorimeter as to an observer appears, the secondary illumination scattered in the tooth to the test point 21 being the primary illumination scattered away equals, the intensity of the primary illumination 22 and the intensity of the secondary illumination 24 should at least at the test point or area 21 as well as on its outer circumference adjoining the light probe tip 17 be approximately the same, and the secondary Illumination should be substantially uniform, or at least not vary greatly.

For example, assume that the light probe tip 17 has a length L which is also the approximate distance from the flat end face 11 of the light-guiding member 7 to the surface of the tooth 9 corresponds to the fact that the light probe tip 17 also has a diameter D, that the light-conducting member 7 also has a Overall diameter W and that the light-guiding member 8 has a diameter d. If the diameters d as well as D are kept constant and the diameter W and the length L are increased, the uniformity of the secondary illumination 24 in the area increases the surface of the tooth 9. It is also assumed, for example, that the dimensions L and W on corresponding Sizes are kept to a number of for example nine separate test points on the tooth of an adult dental Review patient. If then the ratio of the dimensions D and d is changed, the equality of the intensities the primary lighting and the secondary lighting just outside the light probe tip 17 are maintained. It is clear that in order to measure or otherwise visually check a sample with a relatively large surface curvature the dimension D can be comparatively smaller than when measuring a large, fairly flat sample should. - 17 -

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FIG. 4 contains a graphic representation of the curve 26 of the light intensity variable I on the surface of the same plane section as in FIG. 3 through the tooth 9. Between the points 27, 28 of the abscissa, below which the test point or area 21 of the tooth 9 lies, the intensity as a result of the primary illumination 22 has a relatively constant maximum value, as is obtained from a part of the curve P. On both sides of the curve part P there are curve sections S which run downwards and which represent the intensity on the tooth as a result of the secondary illumination 24. Since the intensity of the secondary illumination is essentially uniform or at least does not change significantly in the area of the illuminated tooth surface and since the intensity of the secondary illumination and that of the primary illumination at their meeting points 29, 30 on the curve just inside and just outside the longitudinal extending side walls of the light probe tip 17 at the test point 21 are the same, it is clear that the L, D, W and d parameters are suitably selected to simulate the influence of the ambient lighting. If the intensity of the secondary illumination is too great, the intensity curve from FIG. 4 follows the dashed line S ¹ . If the intensity of the secondary illumination is too low, the intensity curve from FIG. 4 follows the line S ″ outside the area of the primary illumination P between points 27, 28. In each of the last two cases in which the graphic curve from FIG the junction of the primary and secondary lighting has a step, the influence of the ambient lighting is not simulated, and too much or too little secondary light can be scattered to the test point area for recording by the light probe tip 17.

A lot of liquid-like interface material 3 is preferably between the solid or solid end surface 18 of the light probe tip 17 and the test point 21 of the sample, like a tooth 9, on which the end or end face 18 is to be brought to bear for the optical measurement. The material 3 preferably has a refractive index which is approximately the refractive index of the light probe tip 17 or the refractive index of the

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first encountered material on the surface of sample 9, such as for example the refractive index of the surface of a tooth, ent speaks or is in between. In spite of its similarity to liquid, the material 3 is relatively viscous compared to wetting with water, why rapid drainage is prevented; it can also be syrup-like or jelly-like and to form a full cohesive coating on a surface to which the material will be attached. So if the material 3, for example, on the end face 18 of the light probe tip 17 by simply dipping it into a quantity of the material 3 is attached, a suitable amount of the same remains on the end face 18 to last for a sufficient length of time Period of time to coat and allow a technician to apply the coating to a sample. It was found that a suitable interface or intermediate layer material 3 is glycerine, since this is a relatively viscous one or thick material, which tends to flow relatively slowly and which has a good coating on the end area 18 forms. This material is also relatively clear or clear as well as non-toxic and has one suitable for this purpose Refractive index. Of course, however, other boundary or intermediate layer materials with similar properties can also be used to be used.

After a lot of the liquid interface material 3 preferably at the end face 18 or, equivalently, at the test point area 21 of the tooth 9 or another is attached to the test sample, the test end 4 of the light probe 1 can be moved against the sample 9, as shown in FIG is. The solid end face 18 of the light probe tip 17 is essentially up to a smooth contact with the surface of the Sample brought; while it is preferred that as large as possible Part of the end face 18 rests directly on the sample surface, the liquid boundary or intermediate layer 3 tends to form a optical extension of the light probe tip 17 when the end face is not in direct contact with the sample. Usually the end face directly contacts some or all of the peaks 31 of FIG

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Tooth surface, which are exaggerated in Figure 3, and the boundary or intermediate layer material 3 fills the valleys or depressions 32 or other areas of the test point 21 at which the surface 18 is not in direct contact, so that the surface reflection and / or refraction, which otherwise occur and could adversely affect the optical measurements, reduced or eliminated will. Even if the surface of the sample is not very flat or the light probe tip 17 is not exactly at right angles is attached to the surface of the test point area 21, relatively accurate optical measurements of the sample can accordingly be performed.

As described above, the light probe 1 is the present one Invention particularly for use in conjunction with a colorimeter for obtaining quantitative measurements of tooth color of a dental patient. This is particularly true because the end cap 13 can be removed from the end of the light probe is, for example, to sterilize or sterile after use in a patient and then for to exchange a use with another patient. Alternatively, the end cap 13 may be used depending on the cost thereof be designed as a disposable item, so that it is thrown away after use on a patient to get a new one to attach sterile end cap to the end of the light probe 1 and to prepare it for use in another patient. The end cap 13 can also be of different sizes with different Length dimensions L and diameter dimensions D of the light probe tip 17 are designed to be used at any time for a geometric adjustment of the relationships between the primary and secondary lighting, the uniformity of the latter and the size of each optically verifiable individual test point 21. If desired, a quantity of 33 of liquid interface or interlayer material, which can be glycerine or another material with similar properties, as described in connection with the liquid boundary layer material 3, between the surfaces facing one another 11 and 14 of the light conducting members 7, 8 and the end cap

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13 can be arranged in order to intervene the optical coupling in the above in connection with the manner described in connection with the liquid boundary layer material 3. In addition, it should be reflective Coating 19 must be sufficiently thin that it does not constitute a step in the lighting curve 26 at points 29, 3o. The coating 19 can, for example, be an aluminized or aluminum coating on the elongated surface be the light probe tip 17. The exterior of the reflective coating 19 can be blackened or otherwise non-reflective can be made to a peripheral concentration of the secondary illumination 24 running around the test point 21 to avoid.

According to FIGS. 1 and 2, a lamp 34, which is used to generate output light of a constant color temperature, conducts in the colorimeter 6 fed by a regulated meter 35, light through a heat absorbing or infrared filter 36 to the input end 37 of the light-conducting member 7, which via a conventional terminal 38 made of metal or other relatively solid material is coupled to the colorimeter 6. If desired, between the lamp 34 and the input end 37 an adjustable Opening or the like (not shown) for adjusting the intensity of the incident lighting be provided.

The output end 41 of the light conducting member 8 is connected via another conventional connection 42 to the color meter 6 in order to guide the reflected light to a lens 43 which largely collimates the light and guides it along a light path 44 to a rotating color filter wheel 45 which is also shown in FIG. The light that has passed through the color filter wheel is focused or bundled by a further lens 46 onto a measuring photosensitive diode 47, and the signal from this photodiode is fed to a logic and measuring circuit 48 which is synchronized with the rotating color filter wheel 45. If in detail a motor 49 rotates the color filter wheel, which, for example, red, blue and green color filters 45r, 45b, 45g

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Measure Figure 2 contains, is of appropriate light emitting diodes 5od, 51d light emitted occasionally through a rotation synchronization port 52 and through filter alignment openings 53r, 53b, 53g in an opaque circular ring 54 on the color filter wheel directed to energize respective photosensitive transistors 5ot, 51t, as detailed in the above-referenced US patent application is described. The logic and measurement circuit conducts electrical signals to a display device 55, the when operating the colorimeter to measure the red, blue and green optical properties of the sample, for example on corresponding light-emitting diode displays (not shown) Represents values indicative of these properties.

If the light probe 1 and the colorimeter 6 are used, for example, to measure the color properties of a tooth 9, Accordingly, a dentist or dental technician can attach a sterile end cap 13 to the light probe, the fixed end face immerse the light probe tip 17 in an amount of glycerine or the like while holding the cover 12, and then dip the end face 18 largely with the sample in a mutual facility bring, whereby an effective optical coupling with the sample is achieved and the colorimeter automatically the appropriate Measures red, blue, and green color properties of the same.

In Figure 5 is a modified embodiment of a light probe generally designated with the reference number 6o. The light probe 6o includes a first light-conducting member in the form of a forked one light-guiding bundle 61. This has a light-guiding member for the incident lighting with an input end 63, the is aligned by means of a conventional closure 64 to absorb incident light from a light source 65 via an adjustable To receive opening 66 or the like. In addition, the forked one Lichtieitungsbündel 61 a light-guiding member 67 for reflected light with an output end 68 through another Closure 69 is aligned to direct reflected light from a sample to a detector 7o. The two light guiding Links 62 and 67, which have a plastic coating 71

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or shell or the like as protection and to avoid a
Have environmental influences are connected in a conventional connecting member 72 as a randomly distributed light-guiding fiber optic bundle 61. The latter is coupled at another connection point 73 to the secondary lighting light guide member 74, the light input end 75 of which is terminated by a termination 76
is oriented so that light from the light source 65 via a
another adjustable aperture 77 is received. The openings 66
and 77 can be simultaneously or independently adjustable or optionally fixed, and the corresponding ends 63, 75 of the light-guiding members 62, 74 can be relatively movable with respect to the openings in order to adjust the amount of light received thereby. The light-conducting member 74 is preferably also provided with a plastic coating or sheath 78.

The flexible length 79 of the light probe 6o, in which the light-conducting members 61, 74 are concentrically aligned, has a
Protective cover 8o and is closed at the test end 82 by a housing cover 81 made of metal, plastic or the like.

The cover or sheath 81 and the light-conducting parts located therein preferably end in a flat surface, the
a junction 85 with an opposite plane
Surface of the end cap 84 is brought to bear, separated by a liquid boundary or intermediate layer as in
33 in Figure 3, if so desired. The end cap 84 is similar to the end cap 13 described in connection with Figures 1 and 3 and accordingly has a holding part with a translucent ring disc 86 and an elongated, translucent light probe tip 87 that ends in a fixed end surface 88 which is on the surface of a visually inspected
Sample is to be brought to the facility. Extends in end cap 84
however, the reflective coating 89 over the entire length of the light probe tip 87 prevents entry of secondary light and loss of the light reflected from the sample
without inclusion by means of the light conducting member 67 of the bundle

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61 to avoid; and this full length of the non-reflective Coating can be included in the end cap 13 of FIGS. In addition, the diameter dimension D of the light probe tip 87 and the diameter dimension d of the light-guiding bundle 61 preferably equal, so that the entire Primary incident light guided along the light guide glass 62 passes through the light probe tip to illuminate the sample and all of the light reflected from the sample is received by the light probe tip and returned to the beam 61 as well as in the light-guiding member 67 is guided to be measured by the detector.

The light probe 6o can be used in conjunction with a colorimeter, such as the colorimeter 6 described above, to which the Light source 65 and the detector 7o belong. In such a use of the light probe 6o, an amount of liquid boundary or intermediate layer material, such as glycerine or the like, which is designated by the reference number 9o, on the fixed end surface 88 of the light probe tip attached to the optical coupling between the light probe 6o and the sample in the way described above to reinforce.

With the above description in mind, it is now clear that the present invention addresses the optical coupling between a light probe and a sample, simulates the influence of the ambient lighting of a sample while it is with Light of a greater intensity compared to ambient light is measured and it is easier to maintain sterile conditions, when the light probe is used in connection with dental and / or medical procedures.

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Claims (1)

Claims Τ.) Light probe for optically checking a sample by measuring the light coming from it with a light-guiding slide * whose fixed EHd- fczwv end face can be brought to bear directly on at least part of the coarse, * in order to guide light to the sample, and from this absorb reflected light, characterized by a liquid-like Grenzbzw. Interlayer means (3, 9o), between at least a part of the fixed end face (18 * SS) and the sample (9 :) for optically coupling these parts at the points _r where they do not directly abut one another. 2. Light probe according to claim T ₁ , characterized in that the liquid-like boundary or intermediate layer (3 ". 9o) has a substantially clear, relatively viscous or" thick "syrup-like , difficult-to-flow liquid . 1 "light probe according to claim 2" characterized in · that the liquid comprises glycerol, " 4. Light probe according to claim 1 _V, characterized in " that the liquid-like boundary or intermediate _{layer means (3 r} 9o) has a: refractive index, ₇ its size between the refractive indices of the solid end face (TS ₁ -; 880; and the sample (9)) lies. 5. Light sand with an end cap for direct and indirect optical coupling of the light probe to a sample _r characterized, that the end cap (13 ,, 84) light-guiding means (T 7 * ST) with a first end (T41 ₁ the competition at the Light probe. (T _r 6cd1 can be brought to bear, and has a second end (1; S> SS), which is in contact with the sample - 2 - · £ 9} to be brought to the facility. may, - directing zn to substantially all _F captured on one end Iciciit directly to the other end, and thus the light probe CIF 60} and the sample £ 9} largely directly optically coupled to each other ,, and that support means CI51 generally annularly on the Light-guiding means i% l _c 87} extend ^ around the first end (Ή | with the light probe £ 1 _F So} aligned and with extensive contact to hold it, the support means have light-permeable means C16 F 86J -, _r for an indirect Liehtan coupling between the light sand £ 1 _r 6o> l and the sample with the light sand Ct r 6g} can be aligned. 6. Light sand according to claim 5 _F, characterized in that the support means £ 151 collar or input means for receiving the end of the introduced light probe CI e 6σ · ί · have _r with the. first end £ T4} of the light-guiding means CHr 87} comes to rest « _R 7. Light probe according to claim 5 _P characterized in that the light transmitting means £ ΐ 6 SSi _e of the end cap 3 Ci _r S4> a generally annular first surface £ I4 | have " which is essentially in" a plane with the first end of the light-conducting means Ct7 _r 871. S. L-layer sands according to claim 7 _f wherein _r that the light transmissive means IL6> _p 86J * a generally annular second surface £ 2al have ^, the van der first * Surface £ 1! 41 / in a direction toward the second end £ i8 _r 88} of the light-conducting means £ T7 _r S7I 'is shifted _F and that the second end £ t8 _r 88} one. Distance from the second surface C2ct] <has _r whereby the length (L] of the light-conducting; means £ 17} is greater than the thickness of the light-permeable means C16 _r 86} « _f ä * light probe according to claim 8 _F characterized in that the light conducting medium £ T7 _r 87} is located between the first and second ends Ct4 1 18 _P 88} extending fixed longitudinal surface and, on this interior light reflecting means £ 19> Seed} Open TQ-3S23 / ÖS561 oFUQiNAL inspected Ways about a leakage of light from inside the light-conducting. Avoid means (17, 87) through the longitudinal surface " 10. light probe according to claim 9, characterized in that the light reflecting means (19, 89) a reflective coating on the longitudinal surface and a non-reflective one. Coating over the reflective coating to prevent the latter from passing light between the light-permeable means (16, 86) and the sample (9) to reflect em. 11. Lichtsomdie for illuminating a sample and for simulating the influence of ambient lighting, characterized by first licmiJLeitende means (7, 62) for guiding substantially uniform, primary, incident light to a test or test area (21) of an adjacent sample (9) and second light-guiding means (7, 16, 86) for guiding the comparatively less uniform secondary light to the sample (9) in the area of the circumference of the test surface (21), with the aid of such an illumination of the sample 19) the generally uniform lighting influence of the ambient light of the sample (9) is simulated. 12. Light probe according to claim 11, characterized in that the first light-guiding means (7, 62) have a fixed end surface part (17, 18; 87, 88) which can be brought into contact with the sample (9) and the second light-guiding means (7, 16 , 84, 86) have a transparent disk or surface means (16, 86) which is arranged at a distance from the sample (9) relative to the fixed end surface (18, 88} when the end surface is in contact with the sample (9), and which serves to direct the secondary light generally in the same direction as the primary light towards the sample (9) , and that the first and second light directing means have such a relationship that the intensity of the secondary incident light is immediately transmitted to the first end ( 18, 88) adjacent to the sample (9) at most -A- 709-S 29/0650 and is substantially equal to the intensity of the primary light. 13. Light probe according to claim 11, further characterized by reflected Light receiving means (8, 67) for guiding the reflected light from the illuminated sample (9) to a remote location for a visual check of the reflected light. 14. Light probe according to claim 13, characterized in that the first light-guiding means (7) have an elongated, generally have cylindrical, flexible, first light guide, whose input end {37} can be aligned with respect to a light source (34) is to receive incident light therefrom, and the output end of which forms a light output for the light, wherein the first light guide (7) has a hollow interior, and that the means (8) for receiving the reflected light have in the hollow inner region of the first light guide a second light guide, the input end of which is for receiving of the light reflected by the illuminated sample (9) is used and its output end (41) is outside the first Light guide extends to be arranged so that the received reflected light to an optical inspection device (45, 46, 47, 48) is directed. 15. Light probe according to claim 14, characterized in that the The output end of the first light guide (8) and the input end of the second light guide (7) lie in one plane and that the first light-guiding means further comprises an elongate light-guiding tip (17) with opposite end or Have end faces (14, 18), wherein one of the end faces can be brought into contact with a sample (9) and wherein the other of the end faces aligned with both ends of the first and second light guides lying in one plane is, whereby the light-guiding tip (17) from the first Light guide incident primary light directly to the adjacent sample (9) and light reflected from this to the second light guide conducts. - 5 - 709829/0650 16. Light probe according to claim 15, characterized in that the second light-conducting means (7, 16) have light-permeable holding means (13, 15, 16) which are generally annular around the light-guiding tip (17) near the other end face (14) of the same extend, the thickness of the holding means being relatively smaller than the length (L) of the light-guiding tip (17) and wherein the holding means with the remaining part of the Output end of the first light guide are aligned to guide secondary light to the sample (9) and at the same time the to hold the light-guiding tip (17) in its aligned position. 17. Light probe according to claim 16, characterized in that the light-guiding tip (17) and the holding means have a removable end cap (13) and that furthermore transparent liquid Interface means (33) between opposing surfaces of the end cap (13) as well as the first and second light guides are provided for improving the optical coupling between these parts. 18ν light probe according to claim 13, characterized in that the first light conducting means (62) and the means (67) for receiving the reflected light comprise an elongated, generally cylindrical, flexible, bifurcated light guide (61) with first and second opposite ends, wherein the first end with respect to a sample (9) is aligned to the primary illumination thereof, and for receiving hie _r duch reflected light, and wherein the second end of a first portion (63) for receiving primary incident light from a light source (65 ) is alignable, and has a second part (68) which can be aligned for guiding the reflected light to an optical checking device (7o). 19. Light probe according to claim 18, characterized in that the second light-guiding means (74, 86) have a further light guide which has a concentric around a region of the 709829/0650 forked light guide (61) extending part, further a Light input end (75) / which is orientable to receive secondary incident light from a light source (65) and has a generally annular light exit end (86) concentric with the first end of the bifurcated light pipe (61) runs to guide secondary incident light to the sample (9). 20. Light probe according to claim 19, characterized in that the first photoconductive means (62) further an elongated photoconductive tip (87) with opposite end surfaces (88, 14), wherein one of the end faces can be brought into contact with a sample (9) and the other of the End faces with both first ends of the forked light guide is aligned for direct light transmission between this and a sample (9). 21. Light probe according to claim 2o, characterized in that the second light-conducting means (74, 86) are also transparent Having retaining means (86) which are generally annular around the light conducting tip (17) near its other end face (14) extend, the thickness of which is comparatively smaller than the length (L) of the light-guiding tip (8) and the aligned with the light output end of the further light guide (74) are to guide secondary light to a sample (9) and at the same time the light-guiding tip (17) in their aligned position. 22. Light probe according to claim 21, characterized in that the first end of the forked light guide (61) and the light output end the further light guide (74) lie in one plane, the light-guiding tip (87) and the light-permeable Holding means (86) with corresponding surfaces lying in one plane for an aligned positioning the corresponding surface in the first level. 23. Light probe according to claim 22, characterized in that the 709829/0650 5INAL IMSP ^ lS = - light-guiding tip (17) and the holding means (86) a removable End cap (84) and also translucent liquid boundary or intermediate layer means (33) between opposite Surfaces (11, 14) of the end cap (84) and de »in have a plane lying surfaces of the light guide ends to improve the optical coupling between these parts. 24. Light soBde according to claim 11, further characterized by liquid-like boundary or intermediate layer means (3) between the first light-conducting means (61 , 87) and the sample (9) at the test area (21) of the same for optical coupling to the Places where the named parts do not touch each other directly. 709829/0650