Optical System

Abstract

To provide an optical system that can detect abnormalities such as damage to optical elements. [Solution] The optical element 1 comprises a first surface 11 and a second surface 12, with at least one of the first surface 11 and the second surface 12 having a functional surface that performs optical functions; a housing portion 2 that forms a housing 20 together with the optical element 1; a main light irradiation unit 3 disposed inside the housing 20 and having a light source that irradiates the first surface 11 of the optical element 1 with main light; a secondary light irradiation unit 4 having a light source that irradiates the optical element 1 with secondary light of a different wavelength than the main light; and a light detection means 5 that detects light transmitted or reflected by the optical element 1.

Description

Technical Field

[0001] The present invention relates to an optical system apparatus.

Background Art

[0002] In recent years, three-dimensional measurement sensors using the time-of-flight (TOF) method have been adopted in portable devices, automobiles, robots and the like. This is a technique that measures the distance to a target object from the time it takes for light emitted from a light source to the target object to be reflected and return. If the light from the light source uniformly irradiates a predetermined region of the target object, the distance at each irradiated point can be measured, and the three-dimensional structure of the target object can be detected.

[0003] The above optical system apparatus includes an irradiation unit that emits light, an optical element that controls the light from the irradiation unit to a predetermined light distribution, a camera unit that detects light reflected from each point of the target object, and a calculation unit that calculates the distance to the target object from the signal received by the camera unit.

[0004] As the optical element, an element that irradiates diffused light or dot light by devising the arrangement of lenses in a microlens array is used (for example, Patent Document 1 and Patent Document 2). In addition, existing VCSELs, CMOS imagers, CPUs and the like are used for the irradiation unit, camera unit, and calculation unit.

[0005] Further, in such an optical system apparatus, when the light from the irradiation unit is strong like that of a VCSEL, direct irradiation of the light to the eyes or the like involves risks such as blindness, so the apparatus is packaged to prevent the light from leaking directly to the outside.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Disclosure of the Invention

[0007] However, even if the optical system is packaged, if the optical elements are damaged, deformed, or peeled off, there is a risk that light from the illumination area may leak to the outside. In particular, when the optical system is used as a sensor for eye-tracking technology, which detects the position of a person's pupils and tracks what they are looking at in real time, detecting abnormalities in the optical elements is an essential issue.

[0008] Therefore, the present invention aims to provide an optical system that can detect abnormalities such as damage to optical elements. [Means for solving the problem]

[0009] To achieve the above objective, the optical system of the present invention is characterized by comprising: an optical element having a first surface and a second surface, with at least one of the first surface and the second surface having a functional surface that performs an optical function; a housing portion that forms a housing together with the optical element; a main light irradiation unit disposed within the housing and having a light source that irradiates the first surface of the optical element with main light; a secondary light irradiation unit having a light source that irradiates the optical element with secondary light of a different wavelength than the main light; and a light detection means for detecting light transmitted or reflected by the optical element.

[0010] Here, the secondary light irradiator only needs to irradiate the first or second surface of the optical element with secondary light.

[0011] Furthermore, the optical element may have a light-shielding portion on the first or second surface that transmits the primary light and blocks the secondary light. In this case, it is preferable that the secondary light irradiation portion irradiates the first surface of the optical element with secondary light, which is visible light.

[0012] Furthermore, the light detection means may detect light propagating between the first and second surfaces of the optical element.

[0013] Furthermore, the optical element may have a waveguide layer on the first or second surface that propagates at least one of the principal light or the secondary light internally, and the light detection means may detect the light propagating inside the waveguide layer.

[0014] Furthermore, the light detection means may transmit the principal light and be positioned on the optical axis of the principal light irradiation unit.

[0015] Furthermore, the system may include a determination means for determining an abnormality in the optical element based on a change in the light intensity detected by the light detection means. In this case, the determination means may determine the abnormality of the optical element from the change in the light intensity of the secondary light detected by the light detection means. Alternatively, the determination means may determine the abnormality of the optical element from the change in the light intensity of the primary light detected by the light detection means. Alternatively, the determination means may determine the abnormality of the optical element from the change in the integrated value of the light intensity of the secondary light detected by the light detection means. Alternatively, the determination means may determine the abnormality of the optical element from the change in the integrated value of the light intensity of the primary light detected by the light detection means. Alternatively, the determination means may determine the abnormality of the optical element from the change in the ratio of the light intensity of the primary light to the secondary light detected by the light detection means.

[0016] Furthermore, the determination means may determine an abnormality in the main light irradiation area based on the change in the amount of the main light detected by the light detection means. Alternatively, the determination means may determine an abnormality in the main light irradiation area based on the change in the integrated value of the amount of the main light detected by the light detection means. Alternatively, the determination means may determine an abnormality in the main light irradiation area based on the change in the ratio of the amount of the main light to the secondary light detected by the light detection means.

[0017] Furthermore, the determination means may also include a main light irradiation unit cutting means for cutting the lighting circuit of the main light irradiation unit's light source when the determination means determines that there is an abnormality in the optical element. [Effects of the Invention]

[0018] The optical system device of the present invention can easily detect an abnormality of an optical element by utilizing the light from the sub-light irradiation unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] [Figure 1] It is a schematic cross-sectional view showing the optical system device of the present invention in which the light detection means is disposed inside the housing. [Figure 2] It is a schematic cross-sectional view showing the optical system device of the present invention in which the light detection means is disposed outside the housing. [Figure 3] It is a schematic cross-sectional view showing the optical system device of the present invention in which the light detection means detects light propagated inside the optical element. [Figure 4] It is a schematic cross-sectional view showing the optical system device of the present invention in which the light detection means detects light propagated inside the waveguide layer. [Figure 5] It is a schematic cross-sectional view showing the optical system device of the present invention in which the light detection means is located on the optical axis of the main light irradiation unit. DETAILED DESCRIPTION OF EMBODIMENTS FOR CARRYING OUT THE INVENTION

[0020] Hereinafter, the optical system device of the present invention will be described. As shown in Figures 1 to 5, the optical system device of the present invention is mainly composed of an optical element 1, a housing portion 2, a main light irradiation unit 3 that irradiates main light, a sub-light irradiation unit 4 that irradiates sub-light, and a light detection means 5 that detects light. This optical system device is capable of detecting an abnormality of the optical element 1. Here, in the present specification, the abnormality of the optical element 1 corresponds to a state that causes leakage of main light to the outside of the housing 20, and means, for example, breakage, deformation, peeling or the like of the optical element 1.

[0021] As shown in Figure 1, the optical element 1 is composed of a first surface 11 and a second surface 12, and at least one of the first surface 11 and the second surface 12 has a functional surface that performs an optical function. The functional surface is preferably formed on the first surface side. Further, the functional surface may be of any type as long as it can control the main light from the main light irradiation unit 3 to irradiate a predetermined region. For example, the functional surface may control the transmitted main light to form a dot pattern, or to be diffused light, etc. The functional surface corresponds to, for example, an uneven shape such as a microlens array.

[0022] Further, the optical element 1 may be provided with a light shielding portion 8 that transmits main light and blocks secondary light on the first surface 11 or the second surface 12. This can prevent secondary light from leaking through the optical element 1. As the light shielding portion 8, a band-pass filter or the like that transmits main light and blocks secondary light can be used.

[0023] As shown in Figure 1, the housing portion 2 constitutes a housing together with the optical element 1. The housing encloses at least the main light irradiation unit 3, and is configured such that light from the main light irradiation unit 3 does not directly leak to the outside. Further, the housing may enclose the secondary light irradiation unit 4, the light detection means 5, and the like. The housing is configured such that the first surface 11 of the optical element 1 faces the inner side of the housing, and the second surface 12 faces the outer side of the housing. The shape of the housing portion 2 may be any shape as long as the main light irradiation unit 3, the secondary light irradiation unit 4, the light detection means 5, and the like can be enclosed therein. For example, the housing portion 2 may be formed in a bottomed cylindrical shape having an opening that can be closed by the optical element 1. The bottom of the housing portion 2 can have the main light irradiation unit 3, the secondary light irradiation unit 4, the light detection means 5, and the like fixed thereto. The bottom may be a flat surface, or may be formed with a concave groove in which the main light irradiation unit 3, the secondary light irradiation unit 4, the light detection means 5, and the like can be embedded. For the fixing method, a general method such as fixing the main light irradiation unit 3, the secondary light irradiation unit 4, the light detection means 5, and the like to the bottom with an adhesive may be used. As the material of the housing portion 2, a well-known material can be used, but a material with small deformation due to the surrounding environment is preferable. The housing portion 2 may be formed integrally or may be composed of a plurality of members.

[0024] The main light irradiation unit 3 has a light source that irradiates the first surface 11 of the optical element 1 with main light. Therefore, the main light irradiation unit 3 is arranged inside the housing. The main light irradiation unit 3 can be any type of light source that irradiates the optical element 1 with main light of a predetermined wavelength. The main light irradiation unit 3 may be a single light source or multiple light sources. Alternatively, it may be a multiple light source created by passing the light of a single light source through an aperture in which multiple pores are formed. When the irradiation unit is composed of multiple light sources, it is preferable that the light sources be formed on the same plane. The surface from which the light of the irradiation unit 1 is emitted is called the irradiation surface. A specific example of the irradiation unit 1 is a VCSEL (Vertical Cavity Surface Emitting Laser) which can be expected to produce high output with low power. VCSELs include single-emitter VCSELs which have one light source 10 that can irradiate light in a direction perpendicular to the light-emitting surface, and multi-emitter VCSELs which have multiple light sources 10.

[0025] The secondary light irradiator 4 has a light source that irradiates the optical element 1 with secondary light of a different wavelength than the primary light. The secondary light irradiator 4 can be any light source that irradiates the optical element 1 with secondary light of a different wavelength than the primary light, but considering safety for the eyes, it is preferable that it irradiates with visible light or secondary light with a longer wavelength than visible light. The secondary light irradiator 4 may be a single light source or multiple light sources. A specific example of the secondary light irradiator 4 is an LED (Light Emitting Diode) which can be expected to consume little power. The secondary light irradiator 4 may irradiate the first surface 11 of the optical element 1 or the second surface 12. Furthermore, the secondary light irradiator 4 may be located inside the housing as shown in Figures 1(a) and 2(a), or outside the housing as shown in Figures 1(a) and 2(b). If the secondary light irradiation unit 4 is located on the outside of the housing, for example, a member that serves as a waveguide capable of propagating the secondary light from the secondary light irradiation unit 4 may be placed on the second surface 12 side of the optical element 1, and the light propagated through the waveguide may be irradiated onto the second surface 12 of the optical element 1.

[0026] Furthermore, when the light-shielding portion 8 described above is provided on the first surface 11 or the second surface 12 of the optical element 1, it is preferable to place the secondary light irradiating portion 4, which irradiates secondary light that is visible light, on the inside of the housing. With this configuration, if an abnormality such as damage occurs in the optical element 1, visible light will leak from the optical element. Therefore, there is an advantage that the presence or absence of an abnormality in the optical element 1 can be confirmed not only by the light detection means 5, but also by visually checking the leaked visible light.

[0027] The light detection means 5 detects light transmitted or reflected by the optical element 1. The light detection means 5 can be anything that can detect light transmitted or reflected by the optical element 1. For example, a photodiode that can detect changes in light intensity as changes in current can be used. The light detection means 5 may detect only the secondary light, or both the primary and secondary light. Furthermore, depending on the configuration of the optical system, even detecting only the primary light may be sufficient to detect abnormalities in the optical element.

[0028] Furthermore, the light detection means 5 may be positioned inside the housing, as shown in Figure 1, or outside the housing, as shown in Figure 2. When the light detection means 5 is positioned inside the housing, it should be positioned so as not to obstruct the irradiation of the main light from the main light irradiation unit 3 onto the optical element 1. When the light detection means 5 is positioned outside the housing, it should be positioned so as not to obstruct the irradiation of the main light from the main light irradiation unit 3 onto a predetermined area, controlled by the optical element 1. In this case, for example, a member that acts as a waveguide capable of propagating the main light and secondary light may be placed on the second surface 12 side of the optical element 1, and the light detection means 5 may detect the light propagated through the waveguide. The light detection means 5 may also be transparent to the main light. In this case, the light detection means 5 will detect the secondary light. In this case, the light detection means 5 can be positioned on the optical axis of the main light irradiation unit 3, as shown in Figure 3. This ensures reliable detection even if an abnormality such as damage to the optical element 1 occurs on the optical axis of the main light irradiation unit 3.

[0029] When the secondary light irradiator 4 is located on the inside of the housing, the light detection means 5 is located on the inside of the housing to detect the secondary light reflected by the optical element 1, as shown in Figure 1(a). To detect the secondary light transmitted through the optical element 1, the light detection means 5 is located on the outside of the housing, as shown in Figure 2(a). When the secondary light irradiator 4 is located on the outside of the housing, the light detection means 5 is located on the inside of the housing to detect the secondary light transmitted through the optical element 1, as shown in Figure 1(b). To detect the secondary light reflected by the optical element 1, the light detection means 5 is located on the outside of the housing, as shown in Figure 2(b). It is also possible to place the light detection means 5 on both the inside and outside of the housing. In this case, regardless of whether the secondary light irradiator 4 is located on the inside or outside of the housing, both the secondary light transmitted through the optical element 1 and the secondary light reflected by the optical element 1 can be detected.

[0030] Furthermore, the light detection means 5 can also be configured to detect the principal light of the principal light irradiating unit 3. When the light detection means 5 is located on the inside of the housing, it can detect the principal light of the principal light irradiating unit 3 reflected by the optical element 1. When the light detection means 5 is located on the outside of the housing, it can detect the principal light of the principal light irradiating unit 3 that has passed through the optical element 1. When the light detection means 5 is located on both the inside and outside of the housing, it can detect both the principal light that has passed through the optical element 1 and the principal light that has been reflected by the optical element 1.

[0031] Furthermore, the light detection means 5 can also be configured to detect both the primary light from the primary light irradiation unit 3 and the secondary light from the secondary light irradiation unit 4. This makes it possible to detect the ratio of the light intensity of the primary and secondary light, as well as any changes thereto.

[0032] Furthermore, as shown in Figure 4, the light detection means 5 may detect light propagated between the first surface 11 and the second surface 12 of the optical element 1. In this case, the light detection means 5 may detect the propagated principal light, the secondary light, or both the principal and secondary light. Also, by coating the surface of the optical element 1 with a material having a higher refractive index than the material of the optical element 1, or by forming an uneven pattern such as a diffraction grating or prism at a predetermined location on the surface of the optical element 1, it is possible to make it easier for light to propagate into the optical element 1. The light detection means 5 may be placed on the side surface connecting the first surface 11 and the second surface 12 of the optical element 1. It is also possible to place it on the first surface 11 or the second surface 12 of the optical element 1. In this case, in order to extract the light propagated inside the optical element 1, an uneven pattern such as a diffraction grating or prism that diffracts or reflects light to the outside may be formed on the first surface 11 or the second surface 12 of the optical element 1, and the light detection means 5 may be placed at this position.

[0033] Furthermore, as shown in Figure 5, the optical element 1 may also have a waveguide layer formed on the first surface 11 or the second surface 12 that propagates at least one of the principal light or secondary light internally. The light detection means 5 is configured to detect the light propagated inside the waveguide layer. The light detection means 5 may be placed on the side of the waveguide layer. Alternatively, it may be placed on the surface of the waveguide layer. In this case, in order to extract the light propagated inside the waveguide layer, an uneven pattern such as a diffraction grating or prism that diffracts or reflects the light to the outside may be formed on the surface of the waveguide layer, and the light detection means 5 may be placed at this position.

[0034] Furthermore, the optical system of the present invention may further include a determination means 6 that determines an abnormality in the optical element 1 based on a change in the amount of light detected by the light detection means 5. The determination means 5 can be anything that can determine an abnormality in the optical element 1. For example, a processing unit such as a CPU or a computer using a CPU that can perform calculations and data processing based on changes in the amount of light detected by the light detection means 5 can be used.

[0035] The determination means 5 can determine an abnormality in the optical element 1 using any method that can determine this. For example, the determination means can determine an abnormality in the optical element 1 from a change in the amount of secondary light detected by the light detection means 5 or its integrated value, or from a change in the ratio of the amounts of primary light and secondary light. The change may be an increase or a decrease.

[0036] For example, consider a case where damage or other abnormality occurs in the optical element 1, causing an increase in the amount of secondary light transmitted through the optical element 1 and a decrease in the amount of secondary light reflected. In this case, if the light detection means 5 detects the reflected secondary light from the optical element 1, the amount of secondary light will decrease. Also, if the light detection means 5 detects the transmitted secondary light from the optical element 1, the amount of secondary light will increase. Therefore, the determination means 5 can determine that there is an abnormality in the optical element 1 based on the decrease or increase in the amount of secondary light. The determination means 5 can, for example, predetermine threshold values ​​such as the minimum and maximum values ​​of the secondary light amount, and determine that there is an abnormality in the optical element 1 when these threshold values ​​are exceeded.

[0037] Furthermore, if the light detection means 5 detects the principal light, the determination means can also determine an abnormality in the optical element 1 from the change in the amount of principal light detected by the light detection means 5. For example, consider a case where an abnormality such as damage occurs in the optical element 1, causing the amount of principal light transmitted through the optical element 1 to increase and the amount of secondary light reflected to decrease. In this case, if the light detection means 5 detects the reflected light of the principal light from the optical element 1, the amount of principal light will decrease. Also, if the light detection means 5 detects the transmitted light of the principal light from the optical element 1, the amount of principal light will increase. Therefore, the determination means 5 can determine an abnormality in the optical element 1 from the decrease or increase in the amount of principal light. For example, the determination means 5 can predetermine threshold values ​​such as the minimum and maximum values ​​of the principal light amount, and determine that there is an abnormality in the optical element 1 when these threshold values ​​are exceeded.

[0038] Furthermore, the damage or other abnormality to the optical element 1 may be minor, resulting in a small change in light intensity. In this case, the change in the light intensity of the secondary light detected by the light detection means 5 alone may not be sufficient to determine the abnormality of the optical element 1. Therefore, the determination means may determine the abnormality of the optical element 1 from the change in the integrated value of the secondary light intensity detected by the light detection means 5. For example, consider the case where damage or other abnormality occurs in the optical element 1, causing the amount of secondary light transmitted through the optical element 1 to increase and the amount of reflected secondary light to decrease. In this case, if the light detection means 5 detects the reflected light of the secondary light from the optical element 1, the integrated value of the secondary light intensity will decrease. Also, if the light detection means 5 detects the transmitted light of the secondary light from the optical element 1, the integrated value of the secondary light intensity will increase. Therefore, the determination means 5 can determine the abnormality of the optical element 1 from the decrease or increase in the integrated value of the secondary light intensity. The determination means 5 may, for example, predetermine threshold values ​​such as the minimum and maximum values ​​of the integrated value of the secondary light intensity, and determine that there is an abnormality in the optical element 1 when these threshold values ​​are exceeded. As a result, the detection means can detect even minor abnormalities in the optical element 1. The cumulative value is expressed as the product of light intensity and time, but this time can be determined arbitrarily. However, the longer the time, the more accurately minor abnormalities in the optical element 1 can be detected, but the longer the detection time. Conversely, the shorter the time, the faster the detection time, but the more difficult it becomes to detect minor abnormalities. Therefore, it is necessary to set it appropriately according to the application of the optical device. Considering eye protection, it is preferable that this time be at least the time during which visual impairment does not occur even if the light from the main light irradiator 3 is directly shone into the eye.

[0039] Furthermore, if the light detection means 5 has detected the principal light, the determination means can also determine an abnormality in the optical element 1 from the change in the integrated value of the principal light intensity detected by the light detection means 5. For example, consider a case where an abnormality such as damage occurs in the optical element 1, causing the amount of principal light transmitted through the optical element 1 to increase and the amount of secondary light reflected to decrease. In this case, if the light detection means 5 has detected the reflected light of the principal light from the optical element 1, the integrated value of the principal light intensity will decrease. Also, if the light detection means 5 has detected the transmitted light of the principal light from the optical element 1, the integrated value of the principal light intensity will increase. Therefore, the determination means 5 can determine an abnormality in the optical element 1 from the decrease or increase in the integrated value of the principal light intensity. The determination means 5 can, for example, predetermine threshold values ​​such as the minimum and maximum values ​​of the integrated value of the principal light intensity, and determine that there is an abnormality in the optical element 1 when these threshold values ​​are exceeded. In this way, the determination means can also determine even minor abnormalities in the optical element 1. The integrated value is expressed as the product of light intensity and time, but this time can be determined arbitrarily. However, while a longer exposure time allows for the detection of minor abnormalities in the optical element 1, it also increases the time required for detection. Conversely, a shorter exposure time speeds up detection, but makes it more difficult to detect minor abnormalities. Therefore, the exposure time needs to be set appropriately depending on the application of the optical device. Considering eye protection, it is preferable that the exposure time be at least the amount of time during which direct exposure of the eyes with light from the main light irradiator 3 does not cause visual impairment.

[0040] Furthermore, the determination means can also determine an abnormality in the optical element 1 from the change in the ratio of the light intensity of the primary light and the secondary light detected by the light detection means 5. For example, the determination means 5 can pre-determine threshold values ​​such as the minimum and maximum values ​​of the ratio B / A, which is the ratio of the light intensity B of the secondary light to the light intensity A of the primary light, and determine that there is an abnormality in the optical element 1 when the threshold value is exceeded. In this way, the determination means can determine an abnormality in the optical element 1.

[0041] Furthermore, the determination means can also determine an abnormality in the main light irradiation unit 3 from changes in the light intensity or integrated value of the main light detected by the light detection means 5, or from changes in the ratio of the light intensity of the main light to the secondary light. Note that such changes may be increases or decreases. In this specification, an abnormality in the main light irradiation unit 3 means deterioration or malfunction of the main light irradiation unit 3. For example, if the main light irradiation unit 3 deteriorates and the light intensity decreases, the light intensity of the main light and its integrated value detected by the light detection means 5 will decrease. The ratio of the secondary light to the main light, B / A, will also decrease. Therefore, the determination means 5 can determine the deterioration of the main light irradiation unit 3 from the decrease in the light intensity and its integrated value, the decrease in the ratio of the secondary light to the main light, B / A, etc. For example, the determination means 5 can predetermine threshold values ​​for the light intensity of the main light, its integrated value, and the minimum and maximum values ​​of the ratio of the secondary light to the main light, B / A, and determine that there is an abnormality in the main light irradiation unit 3 when these threshold values ​​are exceeded.

[0042] Furthermore, the optical system of the present invention may further include a main light irradiation unit cutting means that cuts the lighting circuit of the light source of the main light irradiation unit 3 when the determination means determines that there is an abnormality in the optical element 1. This allows the lighting of the main light irradiation unit to be stopped immediately when an abnormality in the optical element 1 is determined, thereby preventing dangers such as blindness. The cutting of the lighting circuit can be done in any way that stops the lighting of the light source of the main light irradiation unit 3, for example, by electrically cutting the lighting circuit with software or by physically cutting the lighting circuit by destroying it. [Explanation of symbols]

[0043] 1 Optical element 2. Enclosure 3 Main light irradiation section 4 Secondary light irradiation section 5. Light detection means 6 Judgment means 8. Light-shielding part 11 Page 1 12 Side 2 20 cabinets

Claims

1. A main light irradiating unit that emits the main light, An optical element that controls the main light and irradiates a predetermined area, An optical system having a secondary light irradiation unit that irradiates secondary light used to detect an abnormality in the optical element that causes leakage of the primary light, The main light irradiating unit and the secondary light irradiating unit are packaged within the housing. The optical element is an optical system comprising a light-shielding portion that transmits the primary light and blocks the secondary light.

2. The optical system according to claim 1, wherein the main light irradiation unit is packaged so that the main light does not directly leak to the outside of the optical system.

3. The optical system according to claim 1 or 2, characterized in that the primary light and the secondary light are irradiated onto the optical element in an overlapping manner.

4. The optical system according to claim 1 or 2, characterized in that the irradiation area of ​​the secondary light in the optical element is larger than the irradiation area of ​​the primary light in the optical element.

5. The optical system according to claim 1 or 2, wherein the main light irradiating unit is a VCSEL and the secondary light irradiating unit is an LED.

6. The optical system according to claim 1 or 2, wherein the secondary light irradiation unit irradiates visible light or secondary light with a wavelength longer than visible light.

7. The optical system according to claim 1 or 2, wherein the optical element controls the principal light to a dot pattern or diffuse light.

8. The optical system according to claim 1 or 2, wherein the abnormality of the optical element is damage, deformation, or peeling.

9. The aforementioned secondary light is visible light, The optical system according to claim 1 or 2, wherein the visible light leaks to the outside of the optical system due to an abnormality in the optical element.

10. A three-dimensional measurement sensor utilizing the optical system according to claim 1 or 2.

11. An eye-tracking sensor utilizing the optical system according to claim 1 or 2.

12. An anomaly detection method for detecting an abnormality in an optical element that causes leakage of the principal light from an optical system, which is packaged with a principal light irradiating unit that irradiates the principal light, to the outside of the optical system, The secondary light emitting unit, which emits secondary light, is packaged together with the main light emitting unit within the housing. The optical element includes a light-shielding portion that transmits the primary light and blocks the secondary light, An anomaly detection method characterized by irradiating the optical element with the secondary light emitted from the secondary light irradiation unit.

13. The abnormality detection method according to claim 12, wherein the main light irradiation unit is packaged so that the main light does not directly leak to the outside of the optical system.

14. The abnormality detection method according to claim 12 or 13, characterized in that the primary light and the secondary light are irradiated onto the optical element in an overlapping manner.

15. The optical system according to claim 12 or 13, characterized in that the irradiation area of ​​the secondary light in the optical element is larger than the irradiation area of ​​the primary light in the optical element.

16. The abnormality detection method according to claim 12 or 13, wherein the main light irradiating unit is a VCSEL and the secondary light irradiating unit is an LED.

17. The abnormality detection method according to claim 12 or 13, wherein the abnormality of the optical element is damage, deformation, or peeling.

18. The aforementioned secondary light is visible light, The abnormality detection method according to claim 12 or 13, wherein the visible light leaks to the outside of the optical system due to an abnormality in the optical element.

19. The abnormality detection method according to claim 12 or 13, wherein the abnormality is detected while the main light is being irradiated, and the irradiation of the main light is stopped when the abnormality is detected.

Images