CN104266756A - Broadband infrared scanning beam split device and calibrating method - Google Patents

Abstract

The invention provides a broadband infrared scanning beam split device and a calibrating method. The device comprises an LVF, a clamp, a drive motor, a photoelectric switch, a zero position opening, an external pressing ring and an internal pressing ring. The drive motor drives the clamp with a gradual optical filter to conduct rotating scanning test, the internal pressing ring and the external pressing ring of the clamp press the non-working region of the LVF to conduct fixing, assembly is simple and firm, and the high-speed rotating scanning test can be achieved. Compared with a CVF, by the adoption of the scheme, the coating technology difficulty and coating cost are lowered greatly, and through a corresponding wavelength calibrating algorithm, continuous test of broadband infrared radiation can be achieved.

Description

A kind of broadband infrared scan light-dividing device and calibration steps

Technical field

The invention belongs to infrared radiation spectrophotometric test technical field, in particular a kind of broadband infrared scan light-dividing device and calibration steps.

Background technology

Infrared gradual filter is mainly used in infrared spectral radiant test, at diverse location through different wave length radiation, be used as light-splitting device, require in application that it can cover 3 ~ 5 μm and 8 ~ 14 μm of two infrared atmospheric window mouths, and can fast wavelength sweep be carried out, based on the feature (maximum wavelength is not more than minimum wavelength twice) of coating technique, at present general adopt 3 ~ 4 CVF (circular gradual filter) to be spliced into mode that an annular carries out rotation sweep realizes.But due to CVF coating technique difficulty large (China yet there are no ripe corresponding coating technique), cost is high, limits its widespread use.

Paper " heavy caliber Infrared radiation calibration and error analysis " (infrared and laser engineering, 40th volume the 9th phase, 1624th ~ 1628 pages, in September, 2011), paper " Developing Application of infrared target simulator calibration system " is (infrared with millimeter wave journal, 22nd volume the 4th phase, 251st ~ 255 pages, in August, 2003) and paper " development of infrared spectroradio meter " (infrared and laser engineering, 28th volume the 2nd phase, 14th ~ 17 pages, in April, 1999) all adopt CVF as light-splitting device, coating technique difficulty is large, and cost is high.As shown in Figure 1, incident luminous point 2 converges on CVF1, transmission wave band light intensity be positioned at the infrared eye in dead astern detect, along with CVF1 is under the rotating shaft 3 of motor drives at the uniform velocity in rotary course, detector completes the sweep test of different wave length light intensity.Prior art adopts the mode of CVF light splitting, and CVF device coating technique difficulty is large, and cost is very high, is difficult to be generally used.

Therefore, prior art existing defects, needs to improve.

Summary of the invention

Technical matters to be solved by this invention is for the deficiencies in the prior art, provides a kind of broadband infrared scan light-dividing device and calibration steps.

Technical scheme of the present invention is as follows:

A kind of broadband infrared scan light-dividing device, wherein, comprises fixture, drive motor, optoelectronic switch, outer press ring and inner pressure ring; Described drive motor drive installation has the fixture of gradual filter to carry out rotation sweep test, and the inner pressure ring in fixture and outer press ring are pushed down LVF non-active area and be fixed; When testing, the luminous point that incident camera lens is assembled is beaten on LVF, described fixture rotates under the driving of drive motor, through radiation infrared eye detect, along with the rotation of LVF is to complete the sweep test of different wave length, use optoelectronic switch to detect zero-bit aperture position as zero angle position, all the other positions are determined by counting motor number of steps simultaneously.

A calibration steps for broadband infrared scan light-dividing device, wherein, if the pass that the data recorded after completing the sweep test of different wave length are radiation intensity p and time t/ angle θ is: P=f ₁(t)=f ₂(θ), if try to achieve the funtcional relationship of angle θ corresponding to wavelength X: θ=f ₃(λ) functional relation of namely trying to achieve radiation intensity p and wavelength X in above formula, is substituted into: P=f ₂(f ₃(λ)).

The calibration steps of described broadband infrared scan light-dividing device, wherein, described wavelength and the relation θ of angle=f ₃(λ) computing method are:

If gradual filter operation wavelength is from left to right λ _minλ _max, be then λ in middle position operation wavelength _mid=(λ _min+ λ _max)/2, find the angle of its correspondence to be θ by location ₀, its corresponding relation is: so, at θ ₀wavelength corresponding to+Δ θ position is: λ _mid+ Δ λ, tries to achieve Δ θ and Δ λ relation, namely sets up the corresponding relation of wavelength and angle;

First try to achieve angle delta θ and optical filter length Δ l position corresponding relation:

Formula 1: Δ l=R*sin Δ θ

Formula 1 is substituted into wavelength Δ λ and optical filter length Δ l function of position relational expression, asks the funtcional relationship obtaining wavelength Δ λ and angle delta θ as follows:

Formula 2: Δ λ=Δ l* (λ _max-λ _min)/l=(R*sin Δ θ) * (λ _max-λ _min)/l

Wherein, l is optical filter total length, and R is spot scan radius.

The calibration steps of described broadband infrared scan light-dividing device, wherein, according to formula 2, the angle obtain test and radial coordinate system are converted to the coordinate system of wavelength and radiation, reach the object of wavelength calibration.

The concrete steps of testing the angle that obtains and radial coordinate system and be converted to the coordinate system of wavelength and radiation wherein, are describedly: according to formula 2, be expressed as by angle delta θ wavelength Δ λ by the calibration steps of described broadband infrared scan light-dividing device:

$\mathrm{\Δ\θ}=\arcsin \frac{\mathrm{\Δ\λ}*l}{R*({\mathrm{\λ}}_{\max }-{\mathrm{\λ}}_{\min })};$

Then, angle wavelength is expressed as:

${\mathrm{\θ}}_0+\mathrm{\Δ\θ}={\mathrm{\λ}}_{\mathrm{mid}}+\arcsin \frac{\mathrm{\Δ\λ}*l}{R*({\mathrm{\λ}}_{\max }-{\mathrm{\λ}}_{\min })};$

Then the funtcional relationship of radiation p and wavelength Δ λ is:

$P=f_2({\mathrm{\θ}}_0+\mathrm{\Δ\θ})=f_2\left({\mathrm{\λ}}_{\mathrm{mid}}+\arcsin \frac{\mathrm{\Δ\λ}*l}{R*({\mathrm{\λ}}_{\max }-{\mathrm{\λ}}_{\min })}\right),$

The angle then test obtained and radial coordinate system are converted to the coordinate system of wavelength and radiation.

Adopt such scheme, greatly reduce coating technique difficulty and coating cost, for the wavelength unevenness in LVF scanning process, devise corresponding wavelength calibration algorithm, to realize wide infrared band spectral radiance continuous sweep.

Accompanying drawing explanation

Fig. 1 is that in prior art, three combination CVF scan light splitting schematic diagram.

Fig. 2 is that the present invention three combination LVF scans light-dividing device structural representation.

Fig. 3 is the inventive method medium wavelength calibration schematic diagram.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.

Embodiment 1

The present invention devises one and multi-disc is combined LVF (bar shaped gradual filter) also can carry out high-velocity scanning device for infrared spectral radiant light splitting.As shown in Figure 2, apparatus of the present invention comprise LVF7, fixture 6, drive motor 1, optoelectronic switch 2, zero-bit opening 3, outer press ring 4 and inner pressure ring 5, drive motor 1 drive installation has the fixture 6 of LVF7 to carry out rotation sweep test, inner pressure ring 5 and outer press ring 4 are just in time pushed down LVF7 non-active area and are fixed, assembling is firmly simple, and can realize high-speed rotating scanning test.

In test process, the luminous point that incident camera lens is assembled is beaten on LVF7, the fixture 6 that LVF7 is housed rotates under the driving of drive motor 1, through radiation infrared eye detect, along with the rotation of LVF7 just completes sweep test, meanwhile, detect zero-bit opening 3 position as zero angle position by optoelectronic switch 2, all the other positions are determined by counting motor number of steps.Owing to being rotation sweep, sweep velocity and scanning stabilization all substantially exceed particles mode.

Embodiment 2

On the basis of above-described embodiment, the present invention also provides a kind of calibration steps of broadband infrared scan light-dividing device,

Compared with carrying out scanning light splitting with employing CVF, the present invention greatly reduces coating technique difficulty and coating cost, for the wavelength unevenness in LVF scanning process, devises corresponding wavelength calibration algorithm, to realize wide infrared band spectral radiance continuous sweep.

Carrying out light splitting owing to adopting LVF can keep test wavelength even unlike CVF, adopt in said apparatus test and also have invalid data, to this, devise and adopt said apparatus respective wavelength calibration steps, set up the corresponding relation of wavelength and intensity, to realize wide infrared band spectral radiance follow-on test, as shown in Figure 3:

Because optical filter is uniform angular velocity scanning, therefore, the data recorded be radiation intensity and time/relation of angle: P=f ₁(t)=f ₂(θ), if the functional relation of angle corresponding to wavelength can be obtained: θ=f ₃(λ) functional relation of radiation intensity and wavelength can, so, just be obtained: P=f ₂(f ₃(λ)).

According to the relevant Principle of plating of gradual filter, on bar shaped gradual filter, wavelength is uniform.Even gradual filter from left to right operation wavelength be λ _minλ _max, be so λ in middle position operation wavelength _mid=(λ _min+ λ _max)/2, corresponding angle is θ, and its corresponding relation is: so, at the wavelength that θ+Δ θ position is corresponding be: λ _mid+ Δ λ.

According to trigonometric function relation, first try to achieve angle delta θ and optical filter extension position Δ l corresponding relation, wherein, Δ θ represents the variable quantity of angle θ, and Δ λ represents that the variable quantity of wavelength X is formula 1:

Δl＝R*sinΔθ

Again according to the uniform feature of wavelength on monolithic LVF, above formula is substituted into wavelength and optical filter extension position functional relation, the funtcional relationship that can obtain wavelength Δ λ and angle delta θ is as follows, formula 2:

Δλ＝Δl*(λ _max-λ _min)/l＝(R*sinΔθ)*(λ _max-λ _min)/l

Wherein, l is optical filter total length, and R is spot scan radius, and Δ l represents the variable quantity of l.The concrete steps that the angle obtain test and radial coordinate system are converted to the coordinate system of wavelength and radiation are: according to formula 2, be expressed as by angle delta θ wavelength Δ λ:

Then, angle wavelength is expressed as:

${\mathrm{\θ}}_0+\mathrm{\Δ\θ}={\mathrm{\λ}}_{\mathrm{mid}}+\arcsin \frac{\mathrm{\Δ\λ}*l}{R*({\mathrm{\λ}}_{\max }-{\mathrm{\λ}}_{\min })};$

Then the funtcional relationship of radiation p and wavelength Δ λ is:

the angle then test obtained and radial coordinate system are converted to the coordinate system of wavelength and radiation.

By above-mentioned computing, can obtain the funtcional relationship between angle and wavelength, the angle that finally test can be obtained according to this relational expression and radial coordinate system are converted on the coordinate system of wavelength and radiation, reach the object of wavelength calibration.

Should be understood that, for those of ordinary skills, can be improved according to the above description or convert, and all these improve and convert the protection domain that all should belong to claims of the present invention.

Claims (5)

1. a broadband infrared scan light-dividing device, is characterized in that, comprises fixture, drive motor, optoelectronic switch, outer press ring and inner pressure ring; Described drive motor drive installation has the fixture of gradual filter to carry out rotation sweep test, and the inner pressure ring in fixture and outer press ring are pushed down LVF non-active area and be fixed; When testing, the luminous point that incident camera lens is assembled is beaten on LVF, described fixture rotates under the driving of drive motor, through radiation infrared eye detect, along with the rotation of LVF is to complete the sweep test of different wave length, use optoelectronic switch to detect zero-bit aperture position as zero angle position, all the other positions are determined by counting motor number of steps simultaneously.

2. a calibration steps for broadband infrared scan light-dividing device, is characterized in that, if the pass that the data recorded after completing the sweep test of different wave length are radiation intensity p and time t/ angle θ is: P=f ₁(t)=f ₂(θ), if try to achieve the funtcional relationship of angle θ corresponding to wavelength X: θ=f ₃(λ) functional relation of namely trying to achieve radiation intensity p and wavelength X in above formula, is substituted into: P=f ₂(f ₃(λ)).

3. the calibration steps of broadband infrared scan light-dividing device as claimed in claim 2, is characterized in that, described wavelength and the relation θ of angle=f ₃(λ) computing method are:

If gradual filter operation wavelength is from left to right be then λ in middle position operation wavelength _mid=(λ _min+ λ _max)/2, find the angle of its correspondence to be θ by location ₀, its corresponding relation is: so, at θ ₀wavelength corresponding to+Δ θ position is: λ _mid+ Δ λ, tries to achieve Δ θ and Δ λ relation, namely sets up the corresponding relation of wavelength and angle;

First try to achieve angle delta θ and optical filter length Δ l position corresponding relation:

Formula 1: Δ l=R*sin Δ θ

Formula 1 is substituted into wavelength Δ λ and optical filter length Δ l function of position relational expression, asks the funtcional relationship obtaining wavelength Δ λ and angle delta θ as follows:

Formula 2: Δ λ=Δ l* (λ _max-λ _min)/l=(R*sin Δ θ) * (λ _max-λ _min)/l

Wherein, l is optical filter total length, and R is spot scan radius.

4. the calibration steps of broadband infrared scan light-dividing device as claimed in claim 3, is characterized in that, according to formula 2, the angle obtain test and radial coordinate system are converted to the coordinate system of wavelength and radiation, reach the object of wavelength calibration.

5. the calibration steps of broadband infrared scan light-dividing device as claimed in claim 4, it is characterized in that, describedly by the concrete steps of testing the angle that obtains and radial coordinate system and be converted to the coordinate system of wavelength and radiation be: according to formula 2, angle delta θ wavelength Δ λ is expressed as:

$\mathrm{\Δ\θ}=\arcsin \frac{\mathrm{\Δ\λ}*l}{R*({\mathrm{\λ}}_{\max }-{\mathrm{\λ}}_{\min })};$

Then, angle wavelength is expressed as:

${\mathrm{\θ}}_0+\mathrm{\Δ\θ}={\mathrm{\λ}}_{\mathrm{mld}}+\arcsin \frac{\mathrm{\Δ\λ}*l}{R*({\mathrm{\λ}}_{\max }-{\mathrm{\λ}}_{\min })};$

Then the funtcional relationship of radiation p and wavelength Δ λ is:

$P=f_2({\mathrm{\θ}}_0+\mathrm{\Δ\θ})=f_2({\mathrm{\λ}}_{\mathrm{mid}}+\arcsin \frac{\mathrm{\Δ\λ}*l}{R^{*}({\mathrm{\λ}}_{\max }-{\mathrm{\λ}}_{\min })}),$

The angle then test obtained and radial coordinate system are converted to the coordinate system of wavelength and radiation.