KR102564983B1 - Laser detection auto focusing and optical measuring system having thereof - Google Patents

Abstract

An embodiment relates to an autofocus device and an optical measurement system including the same.
The autofocus device of the embodiment includes a light emitting unit including at least one light emitting element and an optical window disposed on the light emitting element, and a light receiving unit receiving light emitted from the light emitting unit, and the light emitting element includes a vertical resonance laser diode (VCSEL). : Vertical Cavity Surface Emitting Laser), the light emitted from the light emitting device includes a first horizontal angle of view, the optical window includes a base window and a micro lens unit disposed on the base window, and is wider than the first horizontal angle of view An output field of view FOV having a second horizontal angle of view may be included, and the light receiving unit may include a plurality of light receiving elements.
In an embodiment, multi-auto focus may be implemented by expanding the beam angle of view of the light emitting unit, dividing the expanded beam angle of view into a plurality of blocks, and sensing a phase difference.

Description

Auto focus device and optical measurement system including the same {LASER DETECTION AUTO FOCUSING AND OPTICAL MEASURING SYSTEM HAVING THEREOF}

An embodiment relates to an autofocus device.

An embodiment relates to an optical measurement system.

An autofocus device is a technology for obtaining distance information by detecting a position of a subject, and is being developed as an optical measurement system for mobile terminals, cameras, vehicles, and the like.

Among general optical measurement systems, a technology using a laser diode and a photodiode can detect the position of a subject by using a laser diode having excellent linearity.

However, general laser diodes have a beam angle of 21 degrees or less. Therefore, general autofocus devices have been used only for sensing the distance of a subject in a local area in the display area.

Embodiments may provide an autofocus device capable of implementing multi-sensing and an optical measurement system including the same.

Embodiments may provide an autofocus device capable of improving appearance quality and an optical measurement system including the same.

Embodiments may provide an autofocus device capable of improving the reliability of detecting a location of a subject and an optical measurement system including the same.

The autofocus device of the embodiment is

a light emitting unit LD including at least one light emitting device 100 and optical windows 300A, 300B, and 300C disposed on the at least one light emitting device; and a light receiving unit PD receiving light emitted from the light emitting unit, wherein the light emitting element includes a Vertical Cavity Surface Emitting Laser (VCSEL), and the light emitted from the light emitting element has a first horizontal angle of view. The optical window includes a base window 311 and a micro lens unit 313 disposed on the base window, and includes an output field of view FOV having a second horizontal angle of view wider than the first horizontal angle of view. And, the light receiving unit may include a plurality of light receiving elements 200.

In an embodiment, multi-auto focus may be implemented by expanding the beam angle of view of the light emitting unit, dividing the expanded beam angle of view into a plurality of blocks, and sensing a phase difference. In addition, the embodiment includes a light emitting unit; and a housing including a light-receiving unit that is separated from the light-emitting unit with a barrier rib interposed therebetween to receive light emitted from the light-emitting unit; a light emitting element and a second light receiving element disposed within the light emitting unit; a first light receiving element disposed within the light receiving unit; an optical window disposed on the light emitting device; The light emitting device includes a Vertical Cavity Surface Emitting Laser (VCSEL) emitting light at a first horizontal angle of view, and the optical window vertically overlaps the light emitting device and vertically overlaps the second light receiving device. The light emitted from the light emitting element includes a first horizontal angle of view, and the optical window includes a micro lens unit and an output field of view forming a second horizontal angle of view wider than the first horizontal angle of view. and the first light-receiving element and the second light-receiving element pass through the barrier rib and are spaced apart from the IC substrate disposed in the housing, and the first light-receiving element senses the phase difference of the output field having a plurality of block areas. By doing so, it is possible to implement multi-auto focus.

The optical measurement system of the embodiment includes at least one light emitting device 100 and a light emitting unit LD including optical windows 300A, 300B, and 300C disposed on the at least one light emitting device; and a light receiving unit PD receiving light emitted from the light emitting unit, wherein the light emitting element includes a Vertical Cavity Surface Emitting Laser (VCSEL), and the light emitted from the light emitting element has a first horizontal angle of view. The optical window includes a base window 311 and a micro lens unit 313 disposed on the base window, and includes an output field of view FOV having a second horizontal angle of view wider than the first horizontal angle of view. The light receiving unit may include an auto focus device including a plurality of light receiving elements 200 and a display device including a display area displaying an output field of view of the auto focus device.

The autofocus device according to the embodiment may expand the beam view angle of the light emitter, divide the expanded beam view angle into a plurality of blocks, sense the phase difference, widen the auto focus area, and divide the view into a plurality of blocks.

The autofocusing device according to the embodiment may improve autofocusing reliability in a close range of 10 m or less or in a dark environment by extending the beam angle of view of the light emitting unit.

In the embodiment, when light receiving elements and light emitting elements are integrated into one package and applied to various fields, appearance quality can be improved by thinning.

1 is a plan view illustrating an autofocus device according to an exemplary embodiment.
FIG. 2 is a cross-sectional view of the autofocus device taken along line AA of FIG. 1 .
FIG. 3 is a cross-sectional view illustrating exemplary embodiments of an optical window for changing a beam view angle from the light emitting device of FIG. 2 .
4 is a diagram illustrating a microlens unit of an optical window according to an exemplary embodiment.
5 is a diagram illustrating an output field of view (FOV) within a display area of an autofocus device according to an embodiment.
6 is a diagram illustrating an output field of view (FOV) within a display area of an autofocus device according to another embodiment.
7 is a diagram illustrating an output field of view (FOV) within a display area of an autofocus device according to another embodiment.
8 is a diagram showing a plurality of light receiving elements according to an embodiment.
9 is a diagram showing a plurality of light receiving elements according to another embodiment.
10 is a plan view illustrating a light emitting device according to an embodiment.
FIG. 11 is a cross-sectional view of a light emitting device taken along line BB of FIG. 10 .
12 is a plan view illustrating an autofocus device according to another exemplary embodiment.
13 is a perspective view showing a rear side of a mobile terminal according to an embodiment.

Hereinafter, embodiments of the present invention that can specifically realize the above object will be described with reference to the accompanying drawings.

In the description of the embodiment according to the present invention, in the case of being described as being formed on "on or under" of each element, on or under (on or under) or under) includes both elements formed by directly contacting each other or by indirectly placing one or more other elements between the two elements. In addition, when expressed as "on or under", it may include the meaning of not only the upward direction but also the downward direction based on one element.

The semiconductor device may include various electronic devices such as a light emitting device and a light receiving device, and both the light emitting device and the light receiving device may include a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer.

An autofocus device according to an embodiment may include a light emitting element and a light receiving element.

The light emitting device may include, for example, a laser light emitting device such as a Vertical Cavity Surface Emitting Laser (VCSEL).

The photodiode, for example, may include a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, and has a pn junction or pin structure. The photodiode operates by applying reverse bias or zero bias, and when light is incident on the photodiode, electrons and holes are generated and current flows. In this case, the size of the current may be substantially proportional to the intensity of light incident on the photodiode.

1 is a plan view illustrating an autofocus device according to an embodiment, FIG. 2 is a cross-sectional view of the autofocus device taken along line A-A of FIG. 1, and FIG. Cross-sectional views of optical windows according to example embodiments, and FIG. 4 is a diagram illustrating a microlens unit of an optical window according to an exemplary embodiment.

5 is a view showing an FOV within a display area of an autofocus device according to an embodiment, FIG. 6 is a view showing an FOV within a display area of an autofocus device according to another embodiment, and FIG. 7 is a view showing an FOV of an autofocus device according to another embodiment. It is a drawing showing the FOV in the display area.

8 is a diagram showing a plurality of light receiving elements according to an embodiment, and FIG. 9 is a diagram showing a plurality of light receiving elements according to another embodiment.

As shown in FIGS. 1 and 2 , a laser detection auto focusing (LDAF) 10 according to an exemplary embodiment may include a light emitting unit LD and a light receiving unit PD. The autofocus device 10 may detect the distance to the subject by using a phase difference between the light emitted from the light emitting unit LD being reflected on the subject and then incident on the light receiving unit PD after being reflected. Although not shown in the drawings, the autofocus device 10 may include a function of automatically focusing using the distance of the subject.

One of the problems to be solved by the embodiment is to expand the auto focus area by detecting the distance to the subject for each of a plurality of blocks, and detect the distance to the subject by dividing it into a plurality of blocks. It includes optical windows (300A, 300B, 300C) capable of expanding the beam angle of , and provides a phase difference to each of a plurality of blocks divided within a field of view (FOV) defined by the expanded beam angle. It may include a plurality of first light receiving elements 200 that receive light. Here, the first light receiving element 200 includes a function of converting light energy into electrical energy, and includes, for example, a light emitting diode, a photo transistor, a cadmium sulfide (CDS), an avalanche photo diode etc. can be any one. In the embodiment, a photodiode will be described as an example.

One of the problems to be solved by the embodiment is to implement the autofocus device 10 capable of improving appearance quality. To this end, in the embodiment, a plurality of first light receiving elements 200 and second light receiving elements 250 may be integrated on a substrate 15 including a driving circuit. In the embodiment, a plurality of first light receiving elements 200 and second light receiving elements 250 are integrated on a substrate 15 and applied to a mobile terminal, a camera, and a vehicle sensor, so that the auto focus device 10 can be reduced in thickness. there is. That is, when the autofocus device 10 according to the embodiment is applied to various fields, appearance quality can be improved by thinning. The board 15 may include at least one of a PCB made of resin, a PCB having a metal core (MCPCB, Metal Core PCB), and a flexible PCB (FPCB, Flexible PCB), and may be a board on which an IC is mounted. It is not limited to this.

The light emitting part LD may include a light emitting device 100 mounted on a substrate 101 and optical windows 300A, 300B, and 300C. The light emitting device 100 of the light emitting part LD may be a vertical resonance laser diode (VCSEL), but is not limited thereto. The light emitting device 100 may include a constant beam angle. In the case of a vertical resonance laser diode (VCSEL), the light emitting device 100 may include a beam view angle θ1 of 16 degrees to 21 degrees, for example.

The light emitting part LD of the embodiment may include the second light receiving element 250 mounted on the substrate 15 . The second light receiving element 250 may include a function of sensing the luminous flux of the light emitting element 100 by using the light emitted from the light emitting element 100 . That is, the second light receiving device 250 may sense the light of the light emitting device 100 for stable driving of the light emitting device 100 .

<Housing>

The housing 11 of the embodiment may include a function of dividing the light emitting unit LD and the light receiving unit PD and protecting the light emitting device 100 and the first and second light receiving devices 200 and 250 . The housing 11 may include a barrier 11W separating the light receiving part PD and the light emitting part LD. The partition wall 11W may have a function of blocking light emitted from the light emitting part LD and provided to the light receiving part PD within the housing 11 . Accordingly, the barrier rib 11W may improve a problem in that the light emitted from the light emitting part LD is transmitted to the light receiving part PD within the housing 11 .

The housing 11 may be formed by injection molding of synthetic resin or may be formed of metal, such as stainless steel (STS), aluminum (Al), or titanium (Ti).

<Optical Window>

Optical windows 300A, 300B, and 300C may be disposed on the light emitting device 100 . The optical windows 300A, 300B, and 300C may include a function of expanding a first beam view angle θ1 of light emitted from the light emitting device 100 . To this end, the optical windows 300A, 300B, and 300C may include a micro lens unit 313. The optical windows 300A, 300B, and 300C may expand a beam view angle θ1 of 21 degrees or less from the light emitting device 100 to an extended second beam view angle θ2 of 22 degrees to 170 degrees.

The micro lens unit 313 may be formed on the base window 311 . For example, the micro lens unit 313 may be formed on the lower surface of the base window 311. The micro lens unit 313 may face the light emitting device 100. Referring to FIGS. 3(A) and 4 , the micro lens unit 313 of the optical window 300A of the embodiment may include lenses having irregular widths 313w and heights 313h.

A width 313w of each lens of the micro lens unit 313 may be 5 μm to 80 μm. When the width 313w of each lens of the micro lens unit 313 is out of the range of 5 μm to 80 μm, it may be difficult to realize a desired beam angle of view. A height 313h of each lens of the micro lens unit 313 may be 5 μm to 50 μm. When the height 313h of each lens of the micro lens unit 313 is out of the range of 5 μm to 50 μm, it may be difficult to realize a desired beam angle of view.

Referring to FIG. 3(B), the optical window 300B of another embodiment has the technical characteristics of the optical window 300A of FIG. can be hired

The antireflection layer 315 may be disposed on the base window 311 . The antireflection layer 315 may be disposed on a lower surface of the base window 311 . The antireflection layer 315 may be disposed between the base window 311 and the micro lens unit 313 . The anti-reflection layer 315 may include an anti-reflective function. The antireflection layer 315 may reduce light loss in which light emitted from the light emitting device is reflected by the optical window 300B. The antireflection layer 315 may include a function of improving the efficiency of the light emitting unit.

The anti-reflection layer 315 may form an anti-reflection coating film by attaching an anti-reflection coating film or by spin-coating or spray-coating an anti-reflection coating solution. The antireflection layer 315 may include at least one of TiO2, SiO2, Al2O3, Ta2O3, ZrO2, and MgF2, and may be formed as a single layer or multiple layers.

The antireflection layer 315 may improve light emission efficiency of the light emitting unit by improving reflection of light generated at the interface between the base window 311 and the micro lens unit 313 .

Referring to FIG. 3(C), the optical window 300C of another embodiment except for the first and second anti-reflection layers 315 and 317, for example, the micro lens unit 313 is the optical window 300C of FIG. 3(A). The technical features of the window 300A may be employed.

The first antireflection layer 315 may adopt the technical characteristics of the optical window 300B of FIG. 3(B).

The second anti-reflection layer 317 may be disposed opposite to the base window 311 on which the first anti-reflection layer 315 is disposed. For example, the first anti-reflection layer 315 may be disposed on the upper surface of the base window 311 and the second anti-reflection layer 317 may be disposed on the lower surface of the base window 311 . The second anti-reflection layer 317 may have an anti-reflective function. The antireflection layer 317 may reduce light loss in which light emitted from the light emitting device is reflected by the optical window 300C. The second antireflection layer 317 may include a function of improving the efficiency of the light emitting unit.

The second anti-reflection layer 317 may form an anti-reflection coating film by attaching an anti-reflection coating film or by spin-coating or spray-coating an anti-reflection coating solution. The second anti-reflection layer 317 may include at least one of TiO2, SiO2, Al2O3, Ta2O3, ZrO2, and MgF2.

The second antireflection layer 317 can improve the total reflection of light generated between the optical window 310 and the outside air, thereby improving the luminous efficiency of the light emitting unit.

<display area>

Referring to FIGS. 1, 2, and 5 , the display area DA may be defined as an auto focus target area including a subject and a background. For example, in the case of a mobile terminal, it may be an image area displayed on a display device. The autofocus device 10 of the embodiment may include an output field of view (FOV) wider than the field of view of the light emitting device 100 due to the beam angle expanded from the optical windows 300A, 300B, and 300C. The output field of view FOV may be a circular plane within the display area DA. The output field of view (FOV) may be larger than the light emitting field of view (FOV-R) of the light emitting device 100 determined by its own beam angle. Here, the light emitting field of view FOV-R may be locally located in the center of the display area DA.

The output field of view (FOV) of the embodiment may include a plurality of blocks. For example, the output field of view FOV may be divided into first to ninth block areas FOV1 to FOV9. The first to ninth block areas FOV1 to FOV9 may be arranged in a horizontal x vertical direction M x N (M and N are natural numbers other than 0) based on the first block area FOV1. For example, the first to ninth block areas FOV1 to FOV9 are 3 x 3 in first and second directions (X and Y) orthogonal to each other and in directions opposite to the first and second directions (X and Y). It may be arranged, but is not limited thereto. The first to ninth block areas FOV1 to FOV9 according to the embodiment may be in a one-to-one correspondence with the plurality of first light-receiving elements 200 of the light-receiving unit PD. The number or arrangement of blocks is not limited thereto.

Referring to FIGS. 1, 2, and 6, the autofocus device 10 according to another embodiment may include an output field of view (FOV) widened by an expanded beam angle from the optical windows 300A, 300B, and 300C. . A plan view of the output field of view (FOV) within the display area (DA) may have an elliptical shape. For example, a display device including a mobile terminal may include a wide or rectangular display area DA having different horizontal and vertical sizes. In the autofocus device 10 according to another embodiment, the area of the output field of view (FOV) within the display area DA may increase, including the output field of view (FOV) of an elliptical plane corresponding to the major and minor axes of the display area DA. . The output field of view (FOV) may be larger than the light emitting field of view (FOV-R) determined by the beam angle of the light emitting device 100 itself. Here, the light emitting field of view FOV-R may be locally located in the center of the display area DA.

An output field of view (FOV) according to another embodiment may include a plurality of blocks. For example, the output field of view FOV may be divided into first to ninth block areas FOV1 to FOV9. The first to ninth block areas FOV1 to FOV9 may be arranged in a horizontal x vertical direction M x N (M and N are natural numbers other than 0) based on the first block area FOV1. For example, the first to ninth block areas FOV1 to FOV9 are 3 x 3 in first and second directions (X and Y) orthogonal to each other and in directions opposite to the first and second directions (X and Y). It may be arranged, but is not limited thereto. The first to ninth block areas FOV1 to FOV9 according to the embodiment may be in a one-to-one correspondence with the plurality of first light-receiving elements 200 of the light-receiving unit PD. The number or arrangement of blocks is not limited thereto.

Referring to FIGS. 1, 2, and 7 , the autofocus device 10 according to another embodiment may include an output field of view (FOV) widened by an expanded beam angle from the optical windows 300A, 300B, and 300C. there is. The output field of view (FOV) may include a planar shape corresponding to the display area (DA), and may include the same area as the display area (DA). For example, in the autofocus device 10 according to another embodiment, a plane view corresponding to the long and short axes of the display area DA may have the same area as the display area DA, including a rectangular output field of view. . The output field of view (FOV) may be larger than the light emitting field of view (FOV-R) determined by the beam angle of the light emitting device 100 itself. Here, the light emitting field of view FOV-R may be locally located in the center of the display area DA.

An output field of view (FOV) according to another embodiment may include a plurality of blocks. For example, the output field of view FOV may be divided into first to ninth block areas FOV1 to FOV9. The first to ninth block areas FOV1 to FOV9 are arranged in a 3x3 arrangement in first and second directions (X, Y) orthogonal to each other and in directions opposite to the first and second directions (X, Y). It may be, but is not limited thereto. The first to ninth block areas FOV1 to FOV9 according to the embodiment may be in a one-to-one correspondence with the plurality of first light-receiving elements 200 of the light-receiving unit PD.

As described above, the autofocus device 10 of the embodiment is not limited to a local area within the display area DA, including the output field of view (FOV) in which the beam angle of the light emitting device 100 is expanded, and various areas. of multi-auto focus can be implemented.

<Light Receiver>

Referring to FIGS. 1, 2, 5 to 7, and 8 , the light receiving unit PD-A according to the embodiment may include a plurality of first light receiving elements 200 and a light receiving window 320. The light receiving window 320 may have a structure in which the micro lens unit 313 of the optical windows 300A, 300B, and 300C of the light emitting unit LD is omitted. The plurality of first light receiving elements 200 may be of a cell type. The plurality of first light-receiving elements 200 may be photodiodes including semiconductor layers and an absorption layer on a single substrate, and adjacent first light-receiving elements 200 may contact each other.

The plurality of first light receiving elements 200 correspond to the first to ninth block areas FOV1 to FOV9 of the output field of view FOV1 to FOV9 in a one-to-one correspondence, so that the respective phase differences of the first to ninth block areas FOV1 to FOV9 are different. can sense.

Referring to FIGS. 1, 2, 5 to 7, and 9 , the light receiving unit PD-B according to another embodiment may include a plurality of first light receiving elements 200. The plurality of first light-receiving elements 200 may be photodiodes including semiconductor layers and an absorption layer, and the plurality of adjacent first light-receiving elements 200 may be spaced apart from each other.

The plurality of first light receiving elements 200 correspond to the first to ninth block areas FOV1 to FOV9 of the output field of view FOV1 to FOV9 in a one-to-one correspondence, so that the respective phase differences of the first to ninth block areas FOV1 to FOV9 are different. can sense.

The autofocus device 10 according to the embodiment may include a light emitting part LD having an extended beam angle and a light receiving part PD including a plurality of light receiving elements 200 . Accordingly, the autofocus device 10 may implement multi-autofocus by sensing the phase difference of a plurality of blocks.

In the autofocus device 10 of the embodiment, the sensing area is extended from the center to the edge area of the display area DA by the optical windows 300A, 300B, and 300C extending the beam angle of the light emitting element 100, thereby improving autofocus reliability. can be improved. In particular, the embodiment may improve autofocus reliability in a close range of 10 m or less or in a dark environment.

In the embodiment, the plurality of first light receiving elements 200 and the second light receiving elements 250 may be integrated on the IC substrate 15 to make the auto focus device 10 thinner. That is, when the autofocus device 10 according to the embodiment is applied to various fields, appearance quality can be improved by thinning.

FIG. 10 is a plan view of a light emitting device according to an embodiment, and FIG. 11 is a cross-sectional view of the light emitting device taken along line B-B of FIG. 10 .

As shown in FIGS. 10 and 11 , the light emitting device 100 of the autofocus device according to the embodiment may be a vertical resonance laser diode (VCSEL).

The light emitting device 100 may include a light emitting structure 110 and first and second electrodes 120 and 160 .

The first electrode 120 may include an adhesive layer 121 , a substrate 123 and a first conductive layer 125 .

The adhesive layer 121 may include a material capable of eutectic bonding. For example, the adhesive layer 121 may include at least one of AuSn, NiSn, and InAu.

The substrate 123 may be formed of a conductive member, the material being copper (Cu-copper), gold (Au-gold), nickel (Ni-nickel), molybdenum (Mo), copper-tungsten (Cu-W) ), a carrier wafer (eg Si, Ge, AlN, GaAs, ZnO, SiC, etc.). As another example, the substrate 123 may be implemented as a conductive sheet. When the substrate 123 is GaAs, the light emitting structure 110 may be grown on the substrate 123 and the adhesive layer 121 may be omitted.

The first conductive layer 125 may be disposed below the substrate 123 . The first conductive layer 125 is a single layer selected from among Ti, Ru, Rh, Ir, Mg, Zn, Al, In, Ta, Pd, Co, Ni, Si, Ge, Ag, and Au and optional alloys thereof. Or it may be formed in multiple layers.

The light emitting structure 110 may include a first semiconductor layer 111 , an active layer 113 , an aperture layer 114 , and a second semiconductor layer 115 disposed on the first electrode 120 . In the light emitting structure 110, a plurality of compound semiconductor layers may be grown on the first substrate 121, and equipment for growing the plurality of compound semiconductor layers includes an electron beam evaporator, physical vapor deposition (PVD), and chemical vapor deposition), plasma laser deposition (PLD), dual-type thermal evaporator (sputtering), metal organic chemical vapor deposition (MOCVD), etc., but is not limited thereto.

The first semiconductor layer 111 may be implemented with at least one of group 3-5 or group 2-6 compound semiconductors doped with a dopant of the first conductivity type. For example, the first semiconductor layer 111 may be one of GaAs, GaAl, InP, InAs, and GaP, but is not limited thereto. The first semiconductor layer 111 is, for example, a semiconductor having a composition formula of Al _x Ga _{1 - x} As (0 <x <1) / Al _y Ga _{1 - y} As (0 <x <1) (y <x) can be made of material. The first semiconductor layer 111 may be an n-type semiconductor layer doped with a dopant of a first conductivity type, for example, an n-type dopant such as Si, Ge, Sn, Se, or Te. The first semiconductor layer 111 may be a distributed bragg reflector (DBR) having a thickness of λ/4n by alternately disposing different semiconductor layers.

The active layer 113 may be implemented with at least one of group 3-5 or group 2-6 compound semiconductors. For example, the active layer 113 may be one of GaAs, GaAl, InP, InAs, and GaP, but is not limited thereto. When the active layer 113 is implemented as a multi-well structure, the active layer 113 may include a plurality of well layers and a plurality of barrier layers alternately disposed. The plurality of well layers may be formed of, for example, a semiconductor material having a composition formula of In _p Ga _{1 - p} As (0≤p≤1). The barrier layer may be formed of, for example, a semiconductor material having a composition formula of In _q Ga _{1 - q} As (0≤q≤1), but is not limited thereto.

The aperture layer 114 may be disposed on the active layer 113 . The aperture layer 114 may include a circular opening in the center, but is not limited thereto. The aperture layer 114 may include a function of limiting current movement so that current is concentrated in the center of the active layer 113 . That is, the aperture layer 114 can adjust the resonant wavelength and adjust the beam angle vertically emitted from the active layer 113 . The aperture layer 114 may include a dielectric material such as SiO ₂ or Al ₂ O ₃ and may have a higher band gap than the active layer 113 and the first and second semiconductor layers 111 and 115 .

The second semiconductor layer 115 may be implemented with at least one of group 3-5 or group 2-6 compound semiconductors doped with a dopant of the second conductivity type. For example, the second semiconductor layer 115 may be one of GaAs, GaAl, InP, InAs, and GaP, but is not limited thereto. The second semiconductor layer 115 is, for example, a semiconductor having a composition formula of Al _x Ga _{1 - x} As (0 <x < 1) / Al _y Ga _{1 - y} As (0 <x < 1) (y <x) can be made of material. The second semiconductor layer 115 may be a p-type semiconductor layer having a dopant of a second conductivity type, for example, a p-type dopant such as Mg, Zn, Ca, Sr, or Ba. The second semiconductor layer 115 may be a DBR having a thickness of λ/4n by alternately disposing different semiconductor layers. The second semiconductor layer 115 may have a lower reflectance than the first semiconductor layer 111 . For example, the first and second semiconductor layers 111 and 115 may vertically form a resonance cavity by having a reflectance of 90% or more. In this case, light may be emitted to the outside through the second semiconductor layer 115 having a reflectivity lower than that of the first semiconductor layer 111 .

The light emitting device 100 of the embodiment may include the second conductive layer 140 on the light emitting structure 110 . The second conductive layer 140 may be disposed on the second semiconductor layer 115 and may be disposed along an edge of the emission area EA. The second conductive layer 140 may have a circular ring type in a top view, but is not limited thereto and may have an elliptical or polygonal shape. The second conductive layer 140 may have an ohmic contact function. The second conductive layer 140 may be implemented with at least one of group 3-5 or group 2-6 compound semiconductors doped with a dopant of the second conductivity type. For example, the second conductive layer 140 may be one of GaAs, GaAl, InP, InAs, and GaP, but is not limited thereto. The second conductive layer 140 may be a p-type semiconductor layer having a dopant of a second conductivity type, for example, a p-type dopant such as Mg, Zn, Ca, Sr, or Ba.

The light emitting device 100 of the embodiment may include a protective layer 150 on the light emitting structure 110 . The protective layer 150 may be disposed on the second semiconductor layer 115 . The protective layer 150 may vertically overlap the light emitting area EA.

The light emitting device 100 of the embodiment may include an insulating layer 130 . The insulating layer 130 may be disposed on the light emitting structure 110 . The insulating layer 130 may include an insulating material or an insulating resin, such as an oxide, nitride, fluoride, or sulfide of materials such as Al, Cr, Si, Ti, Zn, or Zr. The insulating layer 130 may be selectively formed from, for example, SiO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , and TiO ₂ . The insulating layer 130 may be formed as a single layer or multiple layers, but is not limited thereto.

The second electrode 160 may be disposed on the second conductive layer 140 and the insulating layer 130 . The second electrode 160 may be electrically connected to the second conductive layer 140 . The second electrode 160 is selected from among Ti, Ru, Rh, Ir, Mg, Zn, Al, In, Ta, Pd, Co, Ni, Si, Ge, Ag, and Au and their optional alloys to form a single layer or It can be formed in multiple layers.

12 is a plan view illustrating an autofocus device according to another exemplary embodiment.

As shown in FIG. 12 , an autofocus device according to another embodiment may be separated from a driving unit 415 including a driving circuit. For example, in the autofocus device, the light emitting part LD and the light receiving part PD may be separated from the driving part 415 . An autofocus device according to another embodiment may improve the degree of design freedom in the applied field by the structure of the light emitting part (LD) and the light receiving part (PD) separated from the driving part 415 .

The light emitting part LD and the light receiving part PD may adopt technical features of the auto focus device of FIGS. 1 and 2 .

The aforementioned auto-focusing device has the advantage of being able to perform multi-autofocusing by integrating or separating the light emitting unit (LD) and the light receiving unit (PD) from the driving circuit to reduce the thickness or improve the degree of freedom in design. The autofocus device of another embodiment, which is not limited thereto, has a structure including a plurality of light emitting devices having different output fields of view (FOV) and a light receiving unit sensing a phase difference corresponding to the output field of view (FOV) of each of the plurality of light emitting devices. may also include

13 is a perspective view showing a rear side of a mobile terminal according to an embodiment.

As shown in FIG. 13 , the mobile terminal 500 according to the embodiment may include a camera module 520, a flash module 530, and an autofocus module 10 on the rear side. Here, the auto focus module 10 may adopt the technical features of the auto focus devices of FIGS. 1 to 12 .

The flash module 530 may include a light emitting element emitting light therein. The flash module 530 may be operated by operating a camera of a mobile terminal or by a user's control.

The camera module 520 may include an image capturing function and an auto focus function. For example, the camera module 520 may include an auto focus function using an image.

The auto focus module 10 may include an auto focus function using a laser. The auto-focus module 10 may be mainly used in a condition in which the auto-focus function using the image of the camera module 520 deteriorates, for example, in a close range of 10 m or less or in a dark environment.

The mobile terminal 500 according to the embodiment can improve the reliability of auto focus by detecting the distance to the subject for each of a plurality of blocks, expanding the auto focus area, and dividing the auto focus area into a plurality of blocks to detect the distance to the subject. .

The auto-focus device may be used as a mobile terminal, camera, vehicle sensor, etc., but is not limited thereto, and may be applied to various fields for multi-position detection of a subject's position.

Features, structures, effects, etc. described in the embodiments above are included in at least one embodiment, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, etc. illustrated in each embodiment can be combined or modified with respect to other embodiments by a person having ordinary knowledge in the field to which the embodiments belong. Therefore, contents related to these combinations and modifications should be construed as being included in the scope of the embodiments.

Although the above has been described centering on the embodiments, this is only an example and is not intended to limit the embodiments, and those skilled in the art to which the embodiments belong may be variously illustrated in the above to the extent that they do not deviate from the essential characteristics of the present embodiment. It will be appreciated that variations and applications of branches are possible. For example, each component specifically shown in the embodiment can be modified and implemented. And differences related to these modifications and applications should be construed as being included in the scope of the embodiments set forth in the appended claims.

10: auto focus device
DA: display area
FOV: output field of view
LD: light emitting part
PD: light receiver
100: light emitting element
200: a plurality of first light receiving elements
250: second light receiving element.
300A, 300B, 300C: optical window
311: base window
313: micro lens unit
315: first antireflection layer
317: second antireflection layer

Claims (12)

light emitting part; and a housing including a light-receiving unit that is separated from the light-emitting unit with a barrier rib interposed therebetween and receives light emitted from the light-emitting unit.
a light emitting element and a second light receiving element disposed within the light emitting unit;
a first light receiving element disposed within the light receiving unit;
an optical window disposed on the light emitting device;
The light emitting device includes a Vertical Cavity Surface Emitting Laser (VCSEL) emitting light at a first horizontal angle of view,
The optical window vertically overlaps the light emitting element and does not vertically overlap the second light receiving element,
The light emitted from the light emitting device includes a first horizontal angle of view,
The optical window includes a micro lens unit and an output field of view forming a second horizontal angle of view wider than the first horizontal angle of view,
The first light-receiving element and the second light-receiving element pass through the barrier rib and are spaced apart from the IC substrate disposed in the housing,
wherein the first light-receiving element senses a phase difference of the output field of view having a plurality of block areas to implement multi-auto focus.
According to claim 1,
The autofocus device according to claim 1, wherein the output field of view has a circular, elliptical and rectangular shape in plan view.
According to claim 1,
The first light receiving element includes a plurality of pieces,
The autofocus device according to claim 1 , wherein the plurality of light receiving elements correspond one to one to the plurality of block areas.
According to claim 1,
The micro-lens unit faces the light emitting element, and each lens of the micro-lens unit has a width of 5 μm to 80 μm and a height of 5 μm to 50 μm.
According to claim 4,
The optical window further comprises a first antireflection layer disposed between the base window and the micro lens unit.
According to claim 5,
The optical window further includes a second antireflection layer disposed on an upper surface of the base window.
According to claim 1,
The IC substrate is an autofocus device on which a driving circuit is mounted.
According to claim 1,
The second light receiving element senses the luminous flux or noise of the light emitting element.
According to claim 1,
Further comprising a driving unit in which a driving circuit is mounted on an IC substrate,
The light emitting unit and the light receiving unit are separated from the driving unit.
The autofocus device according to any one of claims 1 to 9; and
An optical measuring system comprising a display device including a display area in which an output field of view of the autofocus device is displayed.
According to claim 10,
The output field of view is disposed within the display area and has an area smaller than the display area.
According to claim 10,
The optical measurement system of claim 1 , wherein the output field of view has an area corresponding to the display area.

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