Optical module, optical device, and method for manufacturing an optical module

Abstract

This optical module includes a splitting surface that transmits part of incident light and reflects at least part of the incident light different from the part of the incident light that is transmitted, the optical module imaging each of the light transmitted through the splitting surface and the light reflected by the splitting surface. The optical module comprises a first optical system and a second optical system. The first optical system comprises, in order from the object side, a forward lens group, an optical path-splitting member having a splitting surface, and a first backward lens group that has a positive refracting power and on which the light transmitted through the splitting surface is incident. The second optical system comprises, in order from the object side, a forward lens group, an optical path-splitting member, and a second backward lens group that has a positive refracting power and on which the light reflected by the splitting surface is incident. One of the first optical system and the second optical system is configured to have an aperture stop on the splitting surface or on the image side of the splitting surface.

Description

[Technical Field]

[0001] This disclosure relates to an optical module, an optical device, and a method for manufacturing an optical module. [Background technology]

[0002] An optical module has been proposed that includes an optical system that splits incident light into a first light and a second light and emits them, a first sensor into which the first light is incident, and a second sensor into which the second light is incident and which has a different function from the first sensor (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2006-324810 [Overview of the project]

[0004] The optical module of this disclosure has a branching surface that transmits a portion of the incident light and reflects at least a portion of the incident light that is different from the portion of the incident light, and is an optical module that images the light transmitted by the branching surface and the light reflected by the branching surface, and comprises, in order from the object side, a first optical system comprising a front lens group, an optical path branching member having a branching surface, and a first rear lens group having positive refractive power into which light transmitted by the branching surface is incident; and a second optical system comprising, in order from the object side, a front lens group, an optical path branching member, and a second rear lens group having positive refractive power into which light reflected by the branching surface is incident, and one of the first optical system and the second optical system is provided with a branching surface or an aperture diaphragm on the image plane side of the branching surface.

[0005] The optical module of this disclosure has a branching surface that transmits a portion of the incident light and reflects at least a portion that is different from the portion of the incident light, and is an optical module that images the light transmitted by the branching surface and the light reflected by the branching surface, and comprises, in order from the object side, a first optical system comprising a front lens group, an optical path branching member having a branching surface, and a first rear lens group having positive refractive power into which light transmitted by the branching surface is incident; and a second optical system comprising, in order from the object side, a front lens group, an optical path branching member, and a second rear lens group having positive refractive power into which light reflected by the branching surface is incident, wherein the number of lenses included in the front lens group is less than the number of lenses included in either the first rear lens group or the second rear lens group.

[0006] The optical module of this disclosure has a branching surface that transmits a portion of the incident light and reflects at least a portion that is different from the incident light, and is an optical module that images the light transmitted by the branching surface and the light reflected by the branching surface, and comprises, in order from the object side, a front lens group, an optical path branching member having a branching surface, and a first rear lens group having positive refractive power into which light transmitted by the branching surface is incident; and a second optical system, in order from the object side, a front lens group, an optical path branching member, and a second rear lens group having positive refractive power into which light reflected by the branching surface is incident, and satisfies the following conditional expression. 0.10 < Df / TL1 ≤ 0.50 however Df: Length along the optical axis from the lens surface closest to the object in the front lens group to the lens surface closest to the image plane in the front lens group. TL1: Length along the optical axis from the lens surface closest to the object to the image plane in the front lens group of the first optical system.

[0007] The optical module of this disclosure has a branching surface that transmits a portion of the incident light and reflects at least a portion that is different from the incident light, and is an optical module that images the light transmitted by the branching surface and the light reflected by the branching surface, and comprises, in order from the object side, a first optical system comprising a front lens group, an optical path branching member having a branching surface, and a first rear lens group having positive refractive power into which light transmitted by the branching surface is incident; and a second optical system comprising, in order from the object side, a front lens group, an optical path branching member, and a second rear lens group having positive refractive power into which light reflected by the branching surface is incident, wherein the front lens group has negative refractive power.

[0008] The present disclosure is a method for manufacturing an optical module having a branching surface that transmits a portion of the incident light and reflects at least a portion of the incident light that is different from the aforementioned portion, and for imaging the light transmitted by the branching surface and the light reflected by the branching surface, wherein the first optical system is arranged in order from the object side to include a front lens group, an optical path branching member having a branching surface, and a first rear lens group having positive refractive power into which light transmitted by the branching surface is incident, and the second optical system is arranged in order from the object side to include a front lens group, an optical path branching member, and a second rear lens group having positive refractive power into which light reflected by the branching surface is incident, and in either the first optical system or the second optical system, an aperture diaphragm is placed on the image plane side of the branching surface. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram illustrating the general configuration of the optical module of this embodiment. [Figure 2] This is a cross-sectional view of the first optical system of the optical module of the first embodiment. [Figure 3] This is a diagram showing the aberrations of the first optical system of the optical module of the first embodiment. [Figure 4] This is a cross-sectional view of the second optical system of the optical module of the first embodiment. [Figure 5] This is a diagram showing the aberrations of the second optical system of the optical module of the first embodiment. [Figure 6]Cross-sectional view of the first optical system of the optical module according to the second embodiment. [Figure 7] Aberration diagrams of the first optical system of the optical module according to the second embodiment. [Figure 8] Cross-sectional view of the second optical system of the optical module according to the second embodiment. [Figure 9] Aberration diagrams of the second optical system of the optical module according to the second embodiment. [Figure 10] Cross-sectional view of the first optical system of the optical module according to the third embodiment. [Figure 11] Aberration diagrams of the first optical system of the optical module according to the third embodiment. [Figure 12] Cross-sectional view of the second optical system of the optical module according to the third embodiment. [Figure 13] Aberration diagrams of the second optical system of the optical module according to the third embodiment. [Figure 14] Schematic diagram of an optical device including the optical module of the present embodiment. [Figure 15] Functional block diagram of the processor of the information processing device included in the optical device of the present embodiment. [Figure 16] Flowchart showing an overview of the manufacturing method of the optical module of the present embodiment.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, an optical module, an optical device, and a manufacturing method of an optical module according to an embodiment of the present application will be described.

[0011] FIG. 1 is a schematic diagram for explaining the schematic configuration of the optical module according to the present embodiment.

[0012] The optical module 1 of the present embodiment includes, in order from the object side, a front lens group GF, an optical path branching member OB having a branching surface BF, and a first rear lens group GR1 into which light incident on the front lens group GF and the optical path branching member OB and transmitted through the branching surface BF enters. The optical module 1 of the present embodiment also includes, in order from the object side, a front lens group GF, an optical path branching member OB, and a second rear lens group GR2 into which light incident on the front lens group GF and the optical path branching member OB and reflected by the branching surface BF enters.

[0013] In FIG. 1, the first optical axis X1 of the first optical system OS1 and the second optical axis X2 of the second optical system OS2 are shown not to overlap each other for the sake of explanation on the object side of the branching surface BF.

[0014] In the optical module 1 of the present embodiment, the light emitted from the front lens group GF enters the optical path branching member OB. The optical path branching member OB is a dichroic prism having a branching surface BF that transmits one of visible light and near-infrared light and reflects the other. Visible light includes, for example, d-line (wavelength 587.6 nm) or g-line (wavelength 435.8 nm), and near-infrared light includes, for example, s-line (wavelength 852.1 nm). The optical module 1 of the present embodiment branches the light incident from the front lens group GF by the optical path branching member OB. The optical path branching member OB may be a dichroic mirror having a branching surface BF.

[0015] The optical module 1 of the present embodiment has a first imaging unit IS1 including a first light receiving surface AS1 on which an imaging element composed of a CCD, a CMOS, or the like is arranged. The first optical system OS1 of the present embodiment forms an image of the light (one of visible light and near-infrared light) emitted from the front lens group GF and transmitted through the branching surface BF of the optical path branching member OB on the first light receiving surface AS1 of the first imaging unit IS1 by the first rear lens group GR1. The first imaging unit IS1 outputs data corresponding to the light imaged on the first light receiving surface AS1.

[0016] The optical module 1 of this embodiment has a second imaging unit IS2 which has a second light-receiving surface AS2 on which an image sensor composed of a CCD or CMOS is arranged. The second optical system OS2 of this embodiment images the light (the other of visible light and near-infrared light) emitted from the front lens group GF, reflected by the branching surface BF of the optical path branching member OB, and totally reflected off the side surface of the optical path branching member OB onto the second light-receiving surface AS2 of the second imaging unit IS2 using the second rear lens group GR2. The second imaging unit IS2 outputs data corresponding to the light imaged onto the second light-receiving surface AS2.

[0017] The optical module 1 of this embodiment can appropriately image the light transmitted through the branching surface BF and the light reflected from the branching surface BF, respectively, using the first optical system OS1 and the second optical system OS2.

[0018] Of the first imaging unit IS1 and the second imaging unit IS2, the data output by the imaging unit that images visible light is used to generate an image representing the appearance of an object. Of the first imaging unit IS1 and the second imaging unit IS2, the imaging unit that images visible light may have an image sensor that receives multiple colors, including d-lines or g-lines, and output a color image representing the appearance of an object. The generated image may be used to detect the appearance of an object.

[0019] The optical module 1 of this embodiment may have a light source LS that emits light of a predetermined wavelength, such as near-infrared light (e.g., s-line). The light source LS is an example of an illumination unit and includes a laser or the like as a light-emitting element. The optical module 1 of this embodiment irradiates an object (not shown) with light of a predetermined wavelength using the light source LS. In the optical module 1 of this embodiment, light from the object is incident on the front lens group GF.

[0020] The imaging unit of the first imaging unit IS1 and the second imaging unit IS2, which forms an image of near-infrared light, can receive light emitted from the light source LS and reflected by the object. The data output by the imaging unit of the first imaging unit IS1 and the second imaging unit IS2, which forms an image of near-infrared light, may be used to detect the distance to the object.

[0021] For example, the data output by the imaging unit, which forms an image of near-infrared light, can be used to detect the time it takes for light emitted from the light source LS to be reflected by the object and received by the imaging unit. The detected time may be used to detect the distance to the object using the Time of Flight (TOF) method.

[0022] Furthermore, the light emitted from the light source LS may have a predetermined pattern, such as stripes or a grid. In this case, the imaging unit that images the near-infrared light outputs data representing the distortion of the pattern of light reflected by the object. The data output by the imaging unit that images the near-infrared light may be used for detecting the distance to the object using a structured light method.

[0023] The optical module 1 of this embodiment is equipped with a light source LS that emits light used to detect the distance to an object. By irradiating the target object with the light used to detect the distance to the object, the distance to the object can be accurately detected using the TOF method or the structured light method.

[0024] In the optical module 1 of this embodiment, both the appearance of the target object and the distance to the object can be detected simultaneously. In the optical module 1 of this embodiment, there is no parallax between the image used to detect the appearance of the object and the image used to detect the distance to the object, so the computational processing required to associate each pixel in the object image with the distance to the surface of the object corresponding to that pixel is reduced.

[0025] In the optical module 1 of this embodiment, it is preferable that the optical system used for detecting the distance to an object has a relatively small F-number and can obtain a relatively bright image. On the other hand, it is preferable that the optical system used for detecting the appearance of an object achieves high optical performance and can obtain an image in which various aberrations are appropriately corrected. It is even more preferable that the optical system used for detecting the appearance of an object has a relatively small F-number and can obtain a relatively bright image.

[0026] Therefore, in the optical module 1 of this embodiment, the F-number of the optical system used for detecting the distance of an object among the first optical system OS1 and the second optical system OS2 may be configured to be less than or equal to the F-number of the optical system used for detecting the appearance of an object among the first optical system OS1 and the second optical system OS2.

[0027] In the optical module 1 of this embodiment, having such a configuration, a brighter image can be used for detecting the distance to an object, and an image with appropriate aberration correction can be used for detecting the appearance of an object.

[0028] Furthermore, it is preferable that the optical module 1 of this embodiment satisfies both of the following conditions. (4) 0.20 < Fno_tof / Fno_img < 1.00 (5) 1.00 < Fno_tof < 2.00 however, Fno_tof: The F-number of the optical system used for detecting the distance to an object, one of the first optical system OS1 and the second optical system OS2. Fno_img: F-number of the optical system used for detecting the appearance of an object, among the first optical system OS1 and the second optical system OS2.

[0029] Conditional equation (4) defines the ratio of the F-number of the optical system used for detecting the distance to an object among the first optical system OS1 and the second optical system OS2 to the F-number of the optical system used for detecting the appearance of the object among the first optical system OS1 and the second optical system OS2. By satisfying conditional equation (4), the optical module 1 of this embodiment can ensure appropriate brightness in both the first optical system OS1 and the second optical system OS2.

[0030] In the optical module 1 of this embodiment, if the value of conditional equation (4) exceeds the upper limit, it becomes impossible to ensure adequate brightness in the optical system used for detecting the distance to an object, which is one of the first optical system OS1 and the second optical system OS2.

[0031] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the upper limit of conditional expression (4) to 1.00. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the upper limit of conditional expression (4) to 0.80, 0.70, and even 0.65.

[0032] Furthermore, in the optical module 1 of this embodiment, if the value of conditional equation (4) falls below the lower limit, it becomes impossible to ensure adequate brightness in the optical system used for detecting the appearance of an object, which is one of the first optical system OS1 and the second optical system OS2.

[0033] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the lower limit of conditional equation (4) to 0.20. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the lower limit of conditional equation (4) to 0.30, 0.40, and even 0.55.

[0034] Conditional equation (5) defines the F-number of the optical system used for detecting the distance to an object among the first optical system OS1 and the second optical system OS2. By satisfying conditional equation (5), the optical module 1 of this embodiment can ensure appropriate brightness in the optical system used for detecting the distance to an object among the first optical system OS1 and the second optical system OS2.

[0035] In the optical module 1 of this embodiment, if the value of conditional expression (5) exceeds the upper limit, it becomes impossible to ensure adequate brightness in the optical system used for detecting the distance to an object, which is one of the first optical system OS1 and the second optical system OS2.

[0036] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the upper limit of conditional expression (5) to 2.00. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the upper limit of conditional expression (5) to 1.80, 1.60, and even 1.40.

[0037] Furthermore, in the optical module 1 of this embodiment, if the value of conditional equation (5) falls below the lower limit, the optical system used for detecting the distance to the object among the first optical system OS1 and the second optical system OS2 becomes too large.

[0038] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the lower limit of conditional expression (5) to 1.00. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the lower limit of conditional expression (5) to 1.10, 1.15, and even 1.20.

[0039] Furthermore, in the optical module 1 of this embodiment, it is preferable that the optical system used for detecting the appearance of an object among the first optical system OS1 and the second optical system OS2 has a cemented lens, and the optical system used for detecting the distance of the image to the object among the first optical system OS1 and the second optical system OS2 consists of only a single lens.

[0040] In the optical module 1 of this embodiment, the optical system used to detect the appearance of an object, among the first optical system OS1 and the second optical system OS2, has a cemented lens, thereby appropriately correcting chromatic aberration of the image used to detect the appearance of an object. Furthermore, in the optical module 1 of this embodiment, the optical system used to detect the distance to an object, among the first optical system OS1 and the second optical system OS2, is configured with only a single lens, thereby enabling miniaturization of the optical system.

[0041] Furthermore, in the optical module 1 of this embodiment, in order to increase the area in which both the distance to the object and the appearance of the object can be detected, it is preferable to reduce the area represented in only one of the images used to detect the distance to the object or the image used to detect the appearance of the object.

[0042] Therefore, it is preferable that the optical module 1 of this embodiment satisfies the following condition. (7) 0.83 < θ1 / θ2 < 1.20 however, θ1: Total field of view of the first optical system OS1 θ2: Full field of view of the second optical system OS2

[0043] Conditional equation (7) defines the ratio of the total field of view of the first optical system OS1 to the total field of view of the second optical system OS2. By satisfying conditional equation (7), the optical module 1 of this embodiment can reduce the region represented in only one of the images used for detecting the appearance of an object and the image used for detecting the distance to the object.

[0044] In the optical module 1 of this embodiment, if the value of conditional equation (7) exceeds the upper limit, the region represented in only one of the images used for detecting the appearance of an object and the image used for detecting the distance to the object becomes too large.

[0045] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the upper limit of conditional expression (7) to 1.20. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the upper limit of conditional expression (7) to 1.15, 1.10, and even 1.05.

[0046] Furthermore, in the optical module 1 of this embodiment, if the value of conditional equation (7) falls below the lower limit, the region represented in only one of the images used for detecting the appearance of an object and the image used for detecting the distance to the object becomes too large.

[0047] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the lower limit of conditional equation (7) to 0.83. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the lower limit of conditional equation (7) to 0.87, 0.91, and even 0.95.

[0048] Furthermore, it is preferable that the optical module 1 of this embodiment satisfies the following conditional expression. (8) 70.0° < θ1 however, θ1: Total field of view of the first optical system OS1

[0049] Conditional equation (8) defines the entire field of view of the first optical system OS1. By satisfying conditional equation (8), the optical module 1 of this embodiment can obtain an image representing a wide area using the first optical system OS1.

[0050] In the optical module 1 of this embodiment, if the value of conditional equation (8) falls below the lower limit, the range represented by the image obtained by the first optical system OS1 becomes too narrow.

[0051] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the lower limit of conditional equation (8) to 70.0°. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the lower limit of conditional equation (8) to 75.0°, 80.0°, and even 90.0°.

[0052] Furthermore, in the optical module 1 of this embodiment, the first optical system OS1 may be used for detecting the appearance of an object, and the second optical system OS2 may be used for detecting the distance to the object. In an optical module 1 having such a configuration, the first optical system OS1, into which light transmitted through the branching surface BF is incident, is not affected by degradation due to reflection of the light beam caused by the surface accuracy of the branching surface BF, so that an image with less degradation can be used for detecting the appearance of an object.

[0053] In this embodiment, the optical module 1 has an aperture diaphragm on the branching surface or on the image plane side of the branching surface in either the first optical system OS1 or the second optical system OS2.

[0054] Furthermore, in the optical module 1 of this embodiment, the first optical system OS1 and the second optical system OS2 may be provided with a branching surface BF or an aperture diaphragm on the image plane side of the branching surface BF.

[0055] The optical module 1 of this embodiment, by including an aperture diaphragm, can obtain a first optical system OS1 or a second optical system OS2 with appropriate optical performance. Furthermore, by positioning the aperture diaphragm on or on the image plane side of the branching surface BF, the peripheral luminous flux of the light incident on the branching surface BF is not restricted, and the attenuation of the peripheral luminous flux relative to the central luminous flux can be reduced.

[0056] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by positioning the aperture diaphragm on the image plane side of at least one lens component located on the image plane side of the optical path branching member OB in the first optical system OS1 and / or the second optical system OS2. In this specification, "lens component" refers to a single lens or a cemented lens formed by joining multiple lenses.

[0057] In the optical module 1 of this embodiment, the number of lenses included in the front lens group GF is less than the number of lenses included in either the first rear lens group GR1 or the second rear lens group GR2.

[0058] In this embodiment, the optical module 1 can be miniaturized by reducing the number of lenses included in the front lens group GF to less than the number of lenses included in either the first rear lens group GR1 or the second rear lens group GR2, and a first optical system OS1 or second optical system OS2 with appropriate optical performance can be obtained.

[0059] Furthermore, in the optical module 1 of this embodiment, the number of lenses included in the front lens group GF may be less than the number of lenses included in the other of the first rear lens group GR1 and the second rear lens group GR2 (the one of the first rear lens group GR1 and the second rear lens group GR2 that has fewer lenses than the number of lenses in the front lens group GF).

[0060] In this embodiment, the optical module 1 can be miniaturized by reducing the number of lenses included in the front lens group GF to less than the number of lenses included in the other of the first rear lens group GR1 and the second rear lens group GR2, and a first optical system OS1 and a second optical system OS2 with appropriate optical performance can be obtained.

[0061] The optical module 1 of this embodiment satisfies the following condition. (2) 0.10 < Df / TL1 ≤ 0.50 however Df: Length along the optical axis from the lens surface closest to the object in the front lens group GF to the lens surface closest to the image plane in the front lens group GF. TL1: Length along the optical axis from the lens surface closest to the object to the image plane of the front lens group GF in the first optical system OS1.

[0062] Conditional equation (2) defines the ratio of the length along the optical axis from the lens surface closest to the object in the front lens group GF to the lens surface closest to the image plane in the front lens group, to the length along the optical axis from the lens surface closest to the object in the front lens group GF to the image plane in the first optical system OS1. In this embodiment, by satisfying conditional equation (2), the optical module 1 can be miniaturized while enabling optical designs suitable for each of the light branches by the branching surface BF.

[0063] In the optical module 1 of this embodiment, if the value of conditional equation (2) exceeds the upper limit, it becomes difficult to perform an optical design suitable for each of the branched beams of light.

[0064] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the upper limit of conditional expression (2) to 0.50. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the upper limit of conditional expression (2) to 0.40, 0.37, and even 0.33.

[0065] Furthermore, in the optical module 1 of this embodiment, if the value of conditional equation (2) falls below the lower limit, the number of lenses required for optical design suitable for each of the branched light beams increases, causing the optical module 1 to become larger.

[0066] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the lower limit of conditional equation (2) to 0.10. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the lower limit of conditional equation (2) to 0.15, 0.17, and even 0.19.

[0067] In the optical module 1 of this embodiment, the front lens group GF has a negative refractive power.

[0068] The optical module 1 of this embodiment can be made smaller in size because the front lens group has negative refractive power.

[0069] Furthermore, it is preferable that the optical module 1 of this embodiment satisfies the following conditional expression. (1) 0.20 < Dst_im / TL1 < 0.50 however, Dst_im: Length from aperture diaphragm ST1 to image plane in the first optical system OS1 TL1: Length along the optical axis from the lens surface closest to the object to the image plane of the front lens group GF in the first optical system OS1.

[0070] Conditional equation (1) defines the ratio of the length from the aperture diaphragm ST1 to the image plane in the first optical system OS1 to the length along the optical axis from the lens surface closest to the object in the front lens group GF of the first optical system OS1 to the image plane. By satisfying conditional equation (1), the optical module 1 of this embodiment can position the aperture diaphragm ST1 in the first optical system OS1 on the image plane side of the first optical system OS1, thereby shortening the overall length.

[0071] In the optical module 1 of this embodiment, if the value of conditional expression (1) exceeds the upper limit, the total length of the first optical system OS1 becomes too long, and as a result, the total length of the optical module 1 becomes too long.

[0072] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the upper limit of conditional expression (1) to 0.50. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the upper limit of conditional expression (1) to 0.47, 0.43, and even 0.40.

[0073] Furthermore, in the optical module 1 of this embodiment, if the value of conditional equation (1) falls below the lower limit, it becomes difficult to correct various aberrations in the first optical system OS1.

[0074] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the lower limit of conditional equation (1) to 0.20. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the lower limit of conditional equation (1) to 0.25, 0.28, and even 0.32.

[0075] Furthermore, it is preferable that the optical module 1 of this embodiment satisfies the following conditional expression. (3) 0.30 < f1R / f2R < 3.33 however, f1R: Focal length of the first rear lens group GR1 f2R: Focal length of the second rear lens group GR2

[0076] Conditional equation (3) defines the ratio of the focal length of the first rear lens group GR1 to the focal length of the second rear lens group GR2. By satisfying conditional equation (3), the optical module 1 of this embodiment can prevent the overall lengths of the first optical system OS1 and the second optical system OS2 from becoming excessively long.

[0077] In the optical module 1 of this embodiment, if the value of conditional equation (3) exceeds the upper limit, the number of lenses in the first rear lens group GR1 increases, and the overall length of the first optical system OS1 becomes too long.

[0078] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the upper limit of conditional expression (3) to 3.33. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the upper limit of conditional expression (3) to 2.85, 2.00, and even 1.67.

[0079] Furthermore, in the optical module 1 of this embodiment, if the value of conditional equation (3) falls below the lower limit, the number of lenses in the second rear lens group GR2 increases, and the overall length of the second optical system OS2 becomes too long.

[0080] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the lower limit of conditional equation (3) to 0.30. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the lower limit of conditional equation (3) to 0.35, 0.50, and even 0.60.

[0081] In the optical module 1 of this embodiment, at least the light on the second optical axis X2 of the light reflected by the branching surface BF of the optical path branching member OB is totally reflected by the total reflection surface TRF of the optical path branching member OB. In the optical module 1 of this embodiment, by providing the total reflection surface TRF, the angle of incidence of the incident light to the branching surface can be reduced, and the difficulty of manufacturing a branching surface with predetermined performance can be reduced.

[0082] Furthermore, in the optical module 1 of this embodiment, the total reflection surface TRF can be the same surface as the surface on which light that has passed through the front lens group GF enters the prism. In the optical module of this embodiment, by making the total reflection surface TRF the same surface as the surface on which light that has passed through the front lens group GF enters the prism, the structure of the prism does not become complicated and can be manufactured relatively easily.

[0083] Furthermore, it is preferable that the optical module 1 of this embodiment satisfies the following conditional expression. (6) 1.00 < Pr1 / f1 < 6.00 however, Pr1: Length along the optical axis from the object-side surface of the optical path branching member OB to the image-plane-side surface of the optical path branching member OB in the first optical system OS1. f1: Focal length of the first optical system OS1

[0084] Conditional equation (6) defines the ratio of the length along the optical axis from the object-side surface of the optical path branching member OB to the image-plane-side surface of the optical path branching member OB in the first optical system OS1 to the focal length of the first optical system OS1. By satisfying conditional equation (6), the optical module 1 of this embodiment can be miniaturized while appropriately brightening the image obtained by the second optical system OS2.

[0085] In the optical module 1 of this embodiment, if the value of conditional equation (6) exceeds the upper limit, the overall length becomes longer relative to the focal length, and the optical module 1 becomes larger.

[0086] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the upper limit of conditional expression (6) to 6.00. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the upper limit of conditional expression (6) to 5.50, 5.00, and even 4.50.

[0087] Furthermore, in the optical module 1 of this embodiment, if the value of conditional equation (6) falls below the lower limit, the peripheral light beam in the second optical system OS2 is restricted, resulting in insufficient brightness of the formed image.

[0088] In the optical module 1 of this embodiment, the effect of this embodiment can be made more reliable by setting the lower limit of conditional expression (6) to 1.00. Furthermore, in order to make the effect of this embodiment even more reliable, it is preferable to set the lower limit of conditional expression (6) to 1.50, 1.80, and even 2.20.

[0089] Furthermore, in the optical module 1 of this embodiment, it is preferable that the first rear lens group GR1 and the second rear lens group GR2 each consist of multiple lenses.

[0090] Furthermore, in the optical module 1 of this embodiment, it is preferable that the front lens group GF has negative refractive power, and the first rear lens group GR1 and the second rear lens group GR2 have positive refractive power. The first optical system OS1 can appropriately correct various aberrations while forming an image with a wide angle of view by ensuring a spacing for the optical path branching member OB between the front lens group GF, which has negative refractive power, and the first rear lens group GR1, which has positive refractive power. The same applies to the second optical system OS2.

[0091] In the optical module 1 of this embodiment, having such a configuration, various aberrations can be appropriately corrected in both the first optical system OS1 and the second optical system OS2.

[0092] With the above configuration, it is possible to realize an optical module that appropriately images both the light transmitted through the branching surface and the light reflected from the branching surface of the incident light.

[0093] The optical device of this embodiment has an optical module 1 with the configuration described above, and detects the appearance of an object and the distance to the object represented by the image formed by the light formed by the optical module 1.

[0094] The optical instrument of this embodiment, having such a configuration, can appropriately image the light transmitted through the branching surface and the light reflected from the branching surface of the incident light, and detect the appearance of the object and the distance to the object represented in each image.

[0095] Furthermore, the optical device of this embodiment comprises an optical module 1 having the configuration described above, a detection unit that detects the appearance of an object and the distance to the object represented by the image formed by the light formed by the optical module 1, a model generation unit that generates shape model information indicating the shape of the object based on the detected distance to the object, and a texture generation unit that generates texture information indicating the appearance of the object based on the detected appearance of the object and associates the generated texture information with the shape model information.

[0096] The optical device of this embodiment, having such a configuration, can appropriately image the light transmitted through the branching surface and the light reflected from the branching surface of the incident light, generate shape model information indicating the shape of the object and texture information indicating the appearance of the object, and associate the texture information with the shape model information.

[0097] The manufacturing method for the optical module of this embodiment is a method for manufacturing an optical module 1 having a branching surface BF that transmits a portion of the incident light and reflects at least a portion that is different from the portion of the incident light, and which images the light transmitted by the branching surface BF and the light reflected by the branching surface BF, wherein the first optical system OS1 is arranged in order from the object side to include a front lens group GF, an optical path branching member OB having a branching surface BF, and a first rear lens group GR1 that has positive refractive power and into which light transmitted by the branching surface BF is incident, and the second optical system OS2 is arranged in order from the object side to include a front lens group GF, an optical path branching member OB, and a second rear lens group GR2 that has positive refractive power and into which light reflected by the branching surface BF is incident, and in either the first optical system OS1 or the second optical system OS2, the branching surface BF or an aperture diaphragm on the image plane side of the branching surface BF is arranged.

[0098] By using this method for manufacturing optical modules, it is possible to manufacture an optical module 1 that appropriately images both the light transmitted through the branching surface and the light reflected from the branching surface of the incident light.

[0099] (Examples of numerical values) The embodiments of this application will be described below with reference to the drawings.

[0100] (First embodiment) In the optical module 1 of the first embodiment, the branching surface BF transmits visible light and reflects near-infrared light. Therefore, in the optical module 1 of the first embodiment, the first optical system OS1 is an optical system that images visible light, and the second optical system OS2 is an optical system that images near-infrared light.

[0101] Figure 2 is a cross-sectional view of the first optical system OS1 of the optical module 1 of the first embodiment.

[0102] The first optical system OS1 of this embodiment includes, in order from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave-shaped negative lens L2, a meniscus-shaped positive lens L3 with its concave surface facing the object side, an optical path branching member OB, a meniscus-shaped positive lens L11 with its convex surface facing the object side, an aperture diaphragm ST1, a meniscus-shaped positive lens L12 with its convex surface facing the object side, a bonded negative lens formed from a biconvex-shaped positive lens L13 and a biconcave-shaped negative lens L14, a meniscus-shaped positive lens L15 with its convex surface facing the object side, and a meniscus-shaped positive lens L16 with its convex surface facing the object side.

[0103] On the image plane I1, the first light-receiving surface AS1 of the first imaging unit IS1, which has an image sensor composed of a CCD or CMOS, is positioned.

[0104] A filter FL1 is positioned between the positive lens L16, which is located closest to the image plane I1, and the image plane I1.

[0105] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2, and positive lens L3 are included in the front lens group GF. Also, positive lens L11, aperture diaphragm ST1, positive lens L12, the cemented negative lens formed by positive lens L13 and negative lens L14, positive lens L15, and positive lens L16 are included in the first rear lens group GR1.

[0106] Table 1-1 below lists the specifications of the first optical system OS1 of this embodiment. In [Lens Specifications] of Table 1-1, m represents the order of the optical surface counted from the object side, r represents the radius of curvature, d represents the surface interval, n(d) represents the refractive index for the d-line, and νd represents the Abbe number for the d-line. A radius of curvature r = ∞ indicates a plane. Also, in [Lens Specifications], an optical surface marked with "*" indicates an aspherical surface.

[0107] In [Aspherical Data], m represents the optical surface corresponding to the aspherical data, K represents the conic constant, and A4 to A10 represent the aspherical coefficients.

[0108] For an aspherical surface, with the height in the direction perpendicular to the optical axis being y, the distance along the optical axis from the tangent plane at the vertex of each aspherical surface to the aspherical surface at height y (sag amount) being S(y), the radius of curvature of the reference sphere (paraxial radius of curvature) being r, the conic constant being K, and the aspherical coefficient of the nth order being An, it is expressed by the following formula (a). In each embodiment, the second-order aspherical coefficient A2 is 0. Also, "E-n" represents "×10 , 8 , , 4 , , 2 , 2 ,

[0110] , , 10 , , 6 , 1 / 2 , , 2 ,

[0111] ".

[0109] (a) S(y) = (y 2 / r) / { 1 + (1 - K × y 2 / r 2 ) 1 / 2} + A4 × y 4 + A6 × y 6 + A8 × y 8 + A10 × y 10

[0110] In [Overall Specifications] of Table 1-1, Fno represents the F-number of the first optical system OS1, f represents the focal length of the entire first optical system OS1, TL represents the distance from the lens surface closest to the object side to the image plane, Y represents the image height, and 2ω represents the total angle of view (degrees). Note that these values described in [Overall Specifications] are values for the d-line.

[0111] The units for focal length f, radius of curvature r, and other lengths listed in Table 1-1 are "mm". However, this is not the only unit, as optical systems can achieve equivalent optical performance even when proportionally enlarged or reduced.

[0112] The reference numerals in Table 1-1 described above will also be used in the tables for the second optical system OS2 of this embodiment and other embodiments, which will be described later.

[0113] (Table 1-1) [Lens Specifications] mrdn(d) νd 1) 23.24716 2.500 1.618 63.34 2) 8.85754 6.000 3) -62.73425 1.300 1.618 63.34 4) 10.07820 2.940 5) -62.37902 5.500 1.755 27.57 6) -30.02650 0.800 7) ∞ 11.000 1.517 63.88 (Optical path branching member OB) 8) ∞ 0.150 9) 18.88785 5.650 1.700 48.10 10) 300.00000 1.540 11> ∞ 1.550 (Aperture diaphragm ST1) 12) 14.36704 2.600 1.697 55.52 13) 313.89814 0.150 14) 15.11805 2.200 1.519 69.89 15) -25.38622 0.400 1.755 27.57 16) 9.06631 0.930 17) 9.42227 2.400 1.623 58.12 18) 42.81721 1.830 *19) 11.33584 4.500 1.623 58.12 *20) 23.57318 4.660 21) ∞ 0.500 1.517 63.88 (Filter FL1) 22) ∞ 0.359 [Aspherical data] m K A4 A6 A8 A10 19) -1.1497 -7.48E-05 -1.27E-06 -8.15E-08 7.15E-10 20) -4.4220 8.96E-05 -2.30E-06 -3.03E-08 3.23E-10 [Overall Specifications] Fno 2.00 f 4.99 TL 59.46 Y 4.01 2ω 92.00

[0114] In this embodiment, the optical path branching member OB is a dichroic prism, and the seventh surface corresponds to the object-side surface, while the eighth surface corresponds to the image-side surface.

[0115] Figure 3 shows the aberrations of the first optical system OS1 of the optical module 1 of the first embodiment.

[0116] In each aberration diagram, the spherical aberration diagram (LONGITUDINAL SPHERICAL ABER.) shows the ratio to the maximum aperture, the astigmatic field curves and distortion diagrams show the half-angle of view value, and the coma aberration diagram shows the ratio to the maximum image height. Each aberration diagram shows the values ​​of the d-line and g-line, respectively. In the astigmatic field curve diagram, S represents the sagittal image plane and T represents the meridional image plane. The same symbols as in the aberration diagrams of this embodiment are used in the aberration diagrams of other embodiments described later.

[0117] From the aberration diagrams, it can be seen that the first optical system OS1 of this embodiment appropriately corrects various aberrations and has high optical performance for the d-line and g-line.

[0118] Figure 4 is a cross-sectional view of the second optical system OS2 of the optical module 1 of the first embodiment.

[0119] The second optical system OS2 of this embodiment includes, in order from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave-shaped negative lens L2, a meniscus-shaped positive lens L3 with its concave surface facing the object side, an optical path branching member OB, a biconvex-shaped positive lens L21, an aperture diaphragm ST2, a meniscus-shaped positive lens L22 with its convex surface facing the object side, a meniscus-shaped negative lens L23 with its concave surface facing the object side, and a biconvex-shaped positive lens L24.

[0120] On the image plane I2, the second light-receiving surface AS2 of the second imaging unit IS2, which has an image sensor composed of a CCD or CMOS, is positioned.

[0121] A filter FL2 is positioned between the positive lens L24, which is located closest to the image plane I2, and the image plane I2.

[0122] In the second optical system OS2 of this embodiment, the negative lens L1, the negative lens L2, and the positive lens L3 are included in the front lens group GF. The positive lens L21, the aperture diaphragm ST2, the positive lens L22, the negative lens L23, and the positive lens L24 are included in the second rear lens group GR2.

[0123] Table 1-2 below lists the specifications of the second optical system OS2 in this embodiment. In the [Lens Specifications] column of Table 1-2, n(s) indicates the refractive index with respect to the s line. This symbol is used similarly in the tables of other embodiments described later.

[0124] (Table 1-2) [Lens Specifications] mrdn(d) νd ns 1) 23.24716 2.500 1.618 63.34 1.610 2) 8.85754 6.000 3) -62.73425 1.300 1.618 63.34 1.610 4) 10.07820 2.940 5) -62.37902 5.500 1.755 27.57 1.735 6) -30.02650 0.800 7) ∞ 32.500 1.517 63.88 1.510 (Optical path branching member OB) 8) ∞ 0.230 9) 15.44687 2.850 1.835 42.73 1.819 10) -300.00000 1.400 11> ∞ 1.650 (Aperture diaphragm ST2) 12) 10.79653 2.850 1.835 42.73 1.819 13) 350.00000 0.920 14) -15.64213 0.500 1.835 42.73 1.819 15) -83.64620 1.190 *16) 300.00000 4.150 1.835 42.73 1.819 *17) -25.21347 3.490 18) ∞ 0.210 1.517 63.88 1.510 (Filter FL2) 19) ∞ 0.343 [Aspherical data] m K A4 A6 A8 A10 16) 9.2225 7.80E-05 2.38E-06 1.06E-06 -3.67E-08 17) -2.9888 4.80E-04 -1.15E-05 3.76E-06 -1.49E-07 [Overall Specifications] Fno 1.18 f 2.81 TL 71.32 Y 2.29 2ω 92.00

[0125] Figure 5 shows the aberration diagrams of the second optical system OS2 of the optical module 1 of the first embodiment. Each aberration diagram shows the value of the s line.

[0126] From the aberration diagrams, it can be seen that the second optical system OS2 of this embodiment appropriately corrects various aberrations and has high optical performance with respect to the s-line.

[0127] (Second example) In the optical module 1 of the second embodiment, the branching surface BF transmits near-infrared light and reflects visible light. Therefore, in the optical module 1 of the second embodiment, the first optical system OS1 is an optical system that images near-infrared light, and the second optical system OS2 is an optical system that images visible light.

[0128] Figure 6 is a cross-sectional view of the first optical system OS1 of the optical module 1 of the second embodiment.

[0129] The first optical system OS1 of this embodiment includes, in order from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave-shaped negative lens L2, a meniscus-shaped positive lens L3 with its convex surface facing the object side, an optical path branching member OB, a meniscus-shaped negative lens L11 with its convex surface facing the object side, an aperture diaphragm ST1, a biconvex-shaped positive lens L12, a meniscus-shaped positive lens L13 with its convex surface facing the object side, and a biconvex-shaped positive lens L14.

[0130] On the image plane I1, the first light-receiving surface AS1 of the first imaging unit IS1, which has an image sensor composed of a CCD or CMOS, is positioned.

[0131] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2, and positive lens L3 are included in the front lens group GF. Also, negative lens L11, aperture diaphragm ST1, positive lens L12, positive lens L13, and positive lens L14 are included in the first rear lens group GR1.

[0132] Table 2-1 below lists the specifications of the first optical system OS1 in this embodiment.

[0133] (Table 2-1) [Lens Specifications] mrdn(d) νd ns 1) 29.68897 1.200 1.640 60.20 1.631 2) 9.70092 5.000 3) -195.75734 1.200 1.618 63.34 1.610 4) 11.92145 1.550 5) 28.18828 2.000 1.755 27.57 1.735 6) 43.38751 1.000 7) ∞ 12.000 1.517 63.88 1.510 (Optical path branching member OB) 8) ∞ 0.500 9) 16.64118 0.350 1.532 48.78 1.523 10) 9.69527 11.748 11> ∞ 0.100 (aperture diaphragm ST1) 12) 16.58651 3.000 1.755 27.57 1.735 13) -531.70077 4.273 14) 10.44070 5.497 1.755 27.57 1.735 15) 14.92879 0.647 *16) 13.31421 5.500 1.774 47.18 1.760 17) -128.00260 4.854 [Aspherical data] m K A4 A6 A8 A10 16) -4.0120 -1.07E-04 -5.73E-06 1.74E-08 6.04E-10 [Overall Specifications] Fno 1.20 f 2.77 TL 60.42 Y 2.20 2ω 92.00

[0134] In this embodiment, the optical path branching member OB is a dichroic prism, and the seventh surface corresponds to the object-side surface, while the eighth surface corresponds to the image-side surface.

[0135] Figure 7 shows the aberration diagrams of the first optical system OS1 of the optical module 1 of the second embodiment. Each aberration diagram shows the value of the s line.

[0136] From the various aberration diagrams, it can be seen that the first optical system OS1 of this embodiment appropriately corrects various aberrations and has high optical performance with respect to the s-line.

[0137] Figure 8 is a cross-sectional view of the second optical system OS2 of the optical module 1 of the second embodiment.

[0138] The second optical system OS2 of this embodiment includes, in order from the object side, a meniscus-shaped negative lens L1 with a convex surface facing the object side, a biconcave-shaped negative lens L2, a meniscus-shaped positive lens L3 with a convex surface facing the object side, an optical path branching member OB, a meniscus-shaped positive lens L21 with a convex surface facing the object side, an aperture diaphragm ST2, a meniscus-shaped negative lens L22 with a convex surface facing the object side, a bonded negative lens formed from a biconvex-shaped positive lens L23 and a biconcave-shaped negative lens L24, a meniscus-shaped positive lens L25 with a convex surface facing the object side, and a meniscus-shaped positive lens L26 with a convex surface facing the object side.

[0139] On the image plane I2, the second light-receiving surface AS2 of the second imaging unit IS2, which has an image sensor composed of a CCD or CMOS, is positioned.

[0140] A filter FL2 is positioned between the positive lens L26, which is located closest to the image plane I2, and the image plane I2.

[0141] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2, and positive lens L3 are included in the front lens group GF. Also, positive lens L21, aperture diaphragm ST2, negative lens L22, the cemented negative lens formed by negative lens L23 and positive lens L24, positive lens L25, and positive lens L26 are included in the second rear lens group GR2.

[0142] Table 2-2 below lists the specifications of the second optical system OS2 in this embodiment.

[0143] (Table 2-2) [Lens Specifications] mrdn(d) νd 1) 29.68900 1.200 1.640 60.19 2) 9.70090 5.000 3) -195.75730 1.200 1.618 63.34 4) 11.92140 1.550 5) 28.18830 2.000 1.755 27.57 6) 43.38750 1.000 7) ∞ 32.500 1.517 63.88 (Optical path branching member OB) 8) ∞ 0.500 9) 12.82210 2.620 1.700 48.10 10) 302.64820 3.760 11> ∞ 0.100 (Aperture diaphragm ST2) 12) 30.12150 0.955 1.651 56.24 13) 26.67870 0.100 14) 10.81720 2.710 1.519 69.89 15) -14.47040 0.350 1.755 27.57 16) 16.24750 0.100 17) 9.11660 1.150 1.620 60.24 18) 10.15080 1.039 *19) 14.74820 5.500 1.620 60.24 *20) 270.84350 1.000 21) ∞ 0.300 1.517 63.88 (Filter FL2) 22) ∞ 7.217 [Aspherical data] m K A4 A6 A8 A10 19) -3.2435 -2.20E-04 -3.59E-06 3.52E-09 2.17E-10 20) 11.0000 -4.40E-05 -1.45E-06 4.57E-08 -2.20E-10 [Overall Specifications] Fno 2.10 f 5.03 TL 71.85 Y 4.02 2ω 92.00

[0144] Figure 9 shows the aberration diagrams of the second optical system OS2 of the optical module 1 of the second embodiment. Each aberration diagram shows the values ​​of the d line and the g line, respectively.

[0145] From the aberration diagrams, it can be seen that the second optical system OS2 of this embodiment appropriately corrects various aberrations and has high optical performance for the d-line and g-line.

[0146] (Third embodiment) In the optical module 1 of the third embodiment, the branching surface BF transmits visible light and reflects near-infrared light. Therefore, in the optical module 1 of the third embodiment, the first optical system OS1 is an optical system that images visible light, and the second optical system OS2 is an optical system that images near-infrared light.

[0147] Figure 10 is a cross-sectional view of the first optical system OS1 of the optical module 1 of the third embodiment.

[0148] The first optical system OS1 of this embodiment includes, in order from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave-shaped negative lens L2, a meniscus-shaped positive lens L3 with its concave surface facing the object side, an optical path branching member OB, a meniscus-shaped positive lens L11 with its convex surface facing the object side, an aperture diaphragm ST1, a meniscus-shaped positive lens L12 with its convex surface facing the object side, a bonded negative lens formed from a biconvex-shaped positive lens L13 and a biconcave-shaped negative lens L14, a meniscus-shaped positive lens L15 with its convex surface facing the object side, and a meniscus-shaped positive lens L16 with its convex surface facing the object side.

[0149] On the image plane I1, the first light-receiving surface AS1 of the first imaging unit IS1, which has an image sensor composed of a CCD or CMOS, is positioned.

[0150] A filter FL1 is positioned between the positive lens L16, which is located closest to the image plane I1, and the image plane I1.

[0151] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2, and positive lens L3 are included in the front lens group GF. Also, positive lens L11, aperture diaphragm ST1, positive lens L12, the cemented negative lens formed by positive lens L13 and negative lens L14, positive lens L15, and positive lens L16 are included in the first rear lens group GR1.

[0152] Table 3-1 below lists the specifications of the first optical system OS1 in this embodiment.

[0153] (Table 3-1) [Lens Specifications] mrdn(d) νd 1) 22.65975 2.000 1.603 60.69 2) 8.58484 6.013 3) -46.67377 0.800 1.519 69.89 4) 10.08192 3.049 5) -69.22039 2.313 1.755 27.57 6) -40.41329 0.988 7) ∞ 17.000 1.517 63.88 (Optical path branching member OB) 8) ∞ 0.384 9) 15.15381 2.574 1.720 50.27 10) 516.88017 4.098 11> ∞ 0.100 (aperture diaphragm ST1) 12) 15.83971 2.165 1.651 56.24 13) 42.97328 0.100 14) 12.34848 2.119 1.519 69.89 15) -21.04824 0.350 1.755 27.57 16) 10.90829 0.100 17) 9.48441 2.289 1.620 60.24 18) 23.82029 1.297 *19) 12.79368 5.503 1.620 60.24 *20) 25.72131 1.000 21) ∞ 0.300 1.517 63.88 (Filter FL1) 22) ∞ 3.960 [Aspherical data] m K A4 A6 A8 A10 19) -2.0024 -1.76E-04 -2.50E-06 -1.86E-08 3.06E-10 20) 11.0000 8.87E-05 -1.45E-06 1.92E-08 4.13E-09 [Overall Specifications] Fno 2.00 f 4.93 TL 58.50 Y 4.01 2ω 92.00

[0154] In this embodiment, the optical path branching member OB is a dichroic prism, and the seventh surface corresponds to the object-side surface, while the eighth surface corresponds to the image-side surface.

[0155] Figure 11 shows the aberration diagrams of the first optical system OS1 of the optical module 1 of the third embodiment. Each aberration diagram shows the values ​​of the d line and the g line, respectively.

[0156] From the aberration diagrams, it can be seen that the first optical system OS1 of this embodiment appropriately corrects various aberrations and has high optical performance for the d-line and g-line.

[0157] Figure 12 is a cross-sectional view of the second optical system OS2 of the optical module 1 of the third embodiment.

[0158] The second optical system OS2 of this embodiment includes, in order from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave-shaped negative lens L2, a meniscus-shaped positive lens L3 with its concave surface facing the object side, an optical path branching member OB, a biconvex-shaped positive lens L21, an aperture diaphragm ST2, a meniscus-shaped positive lens L22 with its convex surface facing the object side, a meniscus-shaped positive lens L23 with its convex surface facing the object side, a meniscus-shaped positive lens L24 with its convex surface facing the object side, and a meniscus-shaped positive lens L25 with its concave surface facing the object side.

[0159] On the image plane I2, the second light-receiving surface AS2 of the second imaging unit IS2, which has an image sensor composed of a CCD or CMOS, is positioned.

[0160] A filter FL2 is positioned between the positive lens L25, which is located closest to the image plane I2, and the image plane I2.

[0161] In the second optical system OS2 of this embodiment, the negative lens L1, the negative lens L2, and the positive lens L3 are included in the front lens group GF. The positive lens L21, the aperture diaphragm ST2, the positive lens L22, the positive lens L23, the positive lens L24, and the positive lens L25 are included in the second rear lens group GR2.

[0162] Table 3-2 below lists the specifications of the second optical system OS2 in this embodiment.

[0163] (Table 3-2) [Lens Specifications] mrdn(d) νd ns 1) 22.65975 2.000 1.603 60.69 1.595 2) 8.58484 6.013 3) -46.67377 0.800 1.519 69.89 1.512 4) 10.08192 3.049 5) -69.22039 2.313 1.755 27.57 1.735 6) -40.41329 0.988 7) ∞ 47.000 1.517 63.88 1.510 (Optical path branching member OB) 8) ∞ 1.805 9) 33.91430 3.017 1.720 50.27 1.708 10) -66.06093 0.100 11> ∞ 0.100 (Aperture diaphragm ST2) 12) 26.49772 2.147 1.623 58.12 1.614 13) 74.01188 0.100 14) 19.60218 2.271 1.593 67.90 1.586 15) 46.09410 0.100 16) 13.36196 2.584 1.487 70.31 1.481 17) 29.13116 4.967 *18) -19.16636 5.496 1.487 70.31 1.481 *19) -9.49217 0.182 20) ∞ 0.300 1.517 63.88 1.510 (Filter FL2) 21) ∞ 3.000 [Aspherical data] m K A4 A6 A8 A10 18) -2.2395 -3.29E-04 3.25E-06 1.17E-07 -4.08E-09 19) 0.3196 -1.85E-05 1.28E-05 -1.34E-07 -8.44E-09 [Overall Specifications] Fno 1.20 f 2.93 TL 88.33 Y 2.29 2ω 92.00

[0164] Figure 13 shows the aberration diagrams of the second optical system OS2 of the optical module 1 of the third embodiment. Each aberration diagram shows the value of the s line.

[0165] From the aberration diagrams, it can be seen that the second optical system OS2 of this embodiment appropriately corrects various aberrations and has high optical performance with respect to the s-line.

[0166] According to the above embodiments, it is possible to realize an optical module that appropriately images both the light transmitted through the branching surface and the light reflected from the branching surface of the incident light.

[0167] The corresponding values ​​for each example are shown below.

[0168] Dst_im is the length from the aperture diaphragm ST1 to the image plane I1 in the first optical system OS1, and TL1 is the length along the optical axis from the lens surface closest to the object in the front lens group GF to the image plane I1 in the first optical system OS1. Df is the length along the optical axis from the lens surface closest to the object in the front lens group GF to the lens surface closest to the image plane in the front lens group GF. f1R is the focal length of the first rear lens group GR1, and f2R is the focal length of the second rear lens group GR2. Fno_tof is the F-number of the optical system used for detecting the distance to the object among the first optical system OS1 and the second optical system OS2, and Fno_img is the F-number of the optical system used for detecting the appearance of the object among the first optical system OS1 and the second optical system OS2. Pr1 is the length along the optical axis from the object-side surface of the optical path branching member OB to the image plane-side surface of the optical path branching member OB in the first optical system OS1, and f1 is the focal length of the first optical system OS1. θ1 is the total field of view (in degrees) of the first optical system OS1, and θ2 is the total field of view (in degrees) of the second optical system OS2.

[0169] Note that the values ​​listed under [Conditional Expression Corresponding Values] are for line d.

[0170] [Conditional expression corresponding value] Examples Conditional Expression 1 2 3 (1) Dst_im / TL1 0.371 0.395 0.330 (2) Df / TL1 0.307 0.181 0.242 (3) f1R / f2R 1.159 0.640 0.805 (4) Fno_tof / Fno_img 0.590 0.571 0.600 (5) Fno_tof 1.180 1.200 1.200 (6) Pr1 / f1 2.206 4.338 3.449 (7) θ1 / θ2 1.000 1.000 1.000 (8) θ1 92.000 92.000 92.000

[0171] The above embodiments illustrate specific examples of the present invention, and the present invention is not limited thereto.

[0172] Next, an optical device equipped with the optical module 1 of this embodiment will be described with reference to Figure 14. Figure 14 is a schematic diagram of an optical device 10 equipped with the optical module 1 of this embodiment.

[0173] The optical device 10 comprises the optical module 1 according to the first embodiment described above and the information processing device 2.

[0174] The light source LS of the optical module 1 emits light containing light of a predetermined wavelength (e.g., s-line) which is imaged by the optical system used for detecting the distance to an object, which is one of the first optical system OS1 and the second optical system OS2.

[0175] In the optical device 10, light including a predetermined wavelength emitted from the light source LS and reflected by an object (not shown) is imaged onto the first light-receiving surface AS1 of the first imaging unit IS1 and the second light-receiving surface AS2 of the second imaging unit IS2 by the first optical system OS1 and the second optical system OS2, respectively. The image sensors in the first imaging unit IS1 and the second imaging unit IS2 convert the light from the object into data.

[0176] The information processing device 2 comprises a communication interface 21, a memory 22, and a processor 23.

[0177] The communication interface 21 has a communication circuit for connecting the optical module 1 to the information processing device 2 in a communicative manner. The communication interface 21 outputs data supplied from the processor 23 to the optical module 1. The communication interface 21 also supplies data received from the optical module 1 to the processor 23.

[0178] Memory 22 is an example of a storage unit and includes volatile semiconductor memory and non-volatile semiconductor memory. Memory 22 stores various data used for processing by the processor 23, such as the field of view of the first optical system OS1 and the second optical system OS2 of the optical module 1, and the number of pixels in the left-right and up-down directions in the data output from the first imaging unit IS1 and the second imaging unit IS2 of the optical module 1. Memory 22 also stores various application programs, such as detection programs for executing detection processing.

[0179] The processor 23 is an example of a control unit and has one or more processors and their peripheral circuits. The processor 23 may further have other arithmetic circuits such as a logic unit, a numerical unit, or a graphics processing unit.

[0180] Figure 15 is a functional block diagram of the processor 23 of the information processing device 2 included in the optical device 10 of this embodiment. The processor 23 of the information processing device 2 has, as functional blocks, a detection unit 231, a model generation unit 232, and a texture generation unit 233.

[0181] The detection unit 231 detects the appearance of the object and the distance to the object, respectively, as represented by the image formed by the light imaged by the optical module 1.

[0182] The detection unit 231 detects the appearance of an object by acquiring data (an image representing the object) output from the first imaging unit IS1 in response to light including d-line or g-line formed by the first optical system OS1.

[0183] Furthermore, the detection unit 231 detects the distance to the object represented by each pixel in the data output from the second imaging unit IS2 in response to the light imaged by the second optical system OS2, based on the time required from the time the light is emitted from the light source LS until the light reflected by the object is received.

[0184] The model generation unit 232 generates shape model information indicating the shape of an object based on the distance from the image formed by the light imaged by the optical module 1 to the detected object. The model generation unit 232 generates shape model information indicating the shape of the object, for example, such that the distance represented by the pixel corresponding to the object in the data output from the second imaging unit IS2 is the distance to the surface of the object.

[0185] The texture generation unit 233 generates texture information representing the appearance of an object based on the appearance of the detected object, and associates the generated texture information with shape model information. The texture generation unit 233 generates texture information representing the appearance of an object from the image information represented by pixels corresponding to the object in the data output from the first imaging unit IS1. The texture generation unit 233 also refers to the respective field of view of the first optical system OS1 and the second optical system OS2 stored in the memory 22, and the number of pixels in the left-right and up-down directions in the data output from the first imaging unit IS1 and the second imaging unit IS2, respectively, and associates each pixel in the data output from the first imaging unit IS1 with each pixel in the data output from the second imaging unit IS2. Then, based on the association between the pixels in the data output from the first imaging unit IS1 and the pixels in the data output from the second imaging unit IS2, the texture generation unit 233 associates the texture information representing the appearance of the object detected from the data output from the first imaging unit IS1 with shape model information representing the shape of the object.

[0186] The optical instrument 10 can appropriately image the light transmitted through the branching surface BF and the light reflected from the branching surface BF of the incident light, and can detect the appearance of the object and the distance to the object represented in each image.

[0187] Furthermore, the optical device 10 can appropriately image the light transmitted through the branching surface BF and the light reflected from the branching surface BF of the incident light, generate shape model information indicating the shape of the object and texture information indicating the appearance of the object, and associate the texture information with the shape model information.

[0188] The optical device 10 may also include an optical module in which the first optical system OS1 images near-infrared light and the second optical system OS2 images visible light, as in the optical module 1 of the second embodiment. In this case, the model generation unit 232 generates shape model information using data output from the first imaging unit IS1, and the texture generation unit 233 generates texture information using data output from the second imaging unit IS2.

[0189] Finally, the general method for manufacturing the optical module 1 of this embodiment will be described based on Figure 16. Figure 16 is a flowchart illustrating the general method for manufacturing the optical module 1 of this embodiment.

[0190] The method for manufacturing the optical module 1 of this embodiment, shown in Figure 16, includes the following steps S1 to S4.

[0191] Step S1: Prepare the front lens group GF, the optical path branching member OB having a branching surface BF, the first rear lens group GR1, and the second rear lens group GR2.

[0192] Step S2: The first optical system OS1 is arranged to include the front lens group GF, the optical path branching member OB, and the first rear lens group GR1.

[0193] Step S3: The second optical system OS2 is arranged to include the front lens group GF, the optical path branching member OB, and the second rear lens group GR2.

[0194] Step S4: In either the first optical system OS1 or the second optical system OS2, an aperture diaphragm is placed on the branching surface BF or on the image plane side of the branching surface BF.

[0195] In the first modified example, step S4A shown below may be performed instead of step S4 in the manufacturing method of the optical module 1 of this embodiment shown in Figure 16.

[0196] Step S4A: Make the number of lenses included in the front lens group GF less than the number of lenses included in one of the first rear lens group GR1 and the second rear lens group GR2.

[0197] In the second modification, instead of step S4 in the manufacturing method of the optical module 1 of the present embodiment shown in FIG. 16, step S4B shown below may be executed.

[0198] Step S4B: Make the first optical system satisfy the following conditional expression. (2) 0.10 < Df / TL1 ≦ 0.50 However Df: The length on the optical axis from the most object-side lens surface of the front lens group to the most image-side lens surface of the front lens group TL1: The length on the optical axis from the most object-side lens surface of the front lens group to the image plane in the first optical system

[0199] In the third modification, instead of step S4 in the manufacturing method of the optical module 1 of the present embodiment shown in FIG. 16, step S4C shown below may be executed.

[0200] Step S4C: Make the front lens group have a negative refractive power.

[0201] <00009​​​​​​​​When the lens surface is aspherical, the aspherical surface may be formed by grinding glass or by a glass mold using a mold having an aspherical shape, or it may be formed on the surface of a resin bonded to the glass surface. In addition, in the optical system of this embodiment, the lens surface may also be a diffractive surface, and the lens may be a refractive index distribution lens (GRIN lens) or a plastic lens.

[0204] Furthermore, an anti-reflective coating having high transmittance over a wide wavelength range may be applied to the lens surfaces of the lenses constituting each optical system of the optical module of this embodiment. This reduces flare and ghosting and achieves high contrast optical performance.

[0205] In each optical system of the optical module of this embodiment, instead of providing an independent member as an aperture diaphragm, the role may be substituted by a lens frame or the like.

[0206] Those skilled in the art should understand that various changes, substitutions, and modifications can be made to this disclosure without departing from its spirit and scope. [Explanation of symbols]

[0207] 1 Optical module OS1 1st optical system OS2 2nd optical system OB optical path branching member BF branching surface GF front lens group GR1 First rear lens group GR2 Second rear lens group ST1, ST2 aperture diaphragm I1, I2 image plane LS light source IS1 First Imaging Unit IS2 Second Imaging Unit 10 Optical equipment 231 Detection unit 232 Model Generation Unit 233 Texture Generation Unit

Claims

1. An optical module having a branching surface that transmits a portion of the incident light and reflects at least a portion of the incident light that is different from the aforementioned portion, and which images the light transmitted by the branching surface and the light reflected by the branching surface, The first optical system comprises, in order from the object side, a front lens group, an optical path branching member having the branching surface, and a first rear lens group having positive refractive power into which light transmitted through the branching surface is incident. The second optical system comprises, in order from the object side, the front lens group, the optical path branching member, and a second rear lens group having positive refractive power into which light reflected at the branching surface is incident. The aforementioned front lens group has a negative lens closest to the object and a positive lens closest to the image plane. One of the first optical system and the second optical system is an optical module equipped with an aperture diaphragm on the branching surface or on the image plane side of the branching surface.

2. The optical module according to claim 1, wherein the first optical system and the second optical system are provided with an aperture diaphragm on the branching surface or on the image plane side of the branching surface.

3. An optical module having a branching surface that transmits a portion of the incident light and reflects at least a portion of the incident light that is different from the aforementioned portion, and which images the light transmitted by the branching surface and the light reflected by the branching surface, The first optical system comprises, in order from the object side, a front lens group, an optical path branching member having the branching surface, and a first rear lens group having positive refractive power into which light transmitted through the branching surface is incident. The second optical system comprises, in order from the object side, the front lens group, the optical path branching member, and a second rear lens group having positive refractive power into which light reflected at the branching surface is incident. The aforementioned front lens group has a negative lens closest to the object and a positive lens closest to the image plane. An optical module in which the number of lenses included in the front lens group is less than the number of lenses included in either the first rear lens group or the second rear lens group.

4. The optical module according to claim 3, wherein the number of lenses included in the front lens group is less than the number of lenses included in the other of the first rear lens group and the second rear lens group.

5. An optical module having a branching surface that transmits a portion of the incident light and reflects at least a portion of the incident light that is different from the aforementioned portion, and which images the light transmitted by the branching surface and the light reflected by the branching surface, The first optical system comprises, in order from the object side, a front lens group, an optical path branching member having the branching surface, and a first rear lens group having positive refractive power into which light transmitted through the branching surface is incident. The second optical system comprises, in order from the object side, the front lens group, the optical path branching member, and a second rear lens group having positive refractive power into which light reflected at the branching surface is incident. The aforementioned front lens group has a negative lens closest to the object and a positive lens closest to the image plane. An optical module that satisfies the following conditions. 0.10 < Df / TL1 ≦ 0.50 however Df: Length along the optical axis from the lens surface closest to the object in the front lens group to the lens surface closest to the image plane in the front lens group. TL1: The length along the optical axis from the lens surface closest to the object to the image plane of the front lens group in the first optical system.

6. The optical module according to any one of claims 3 to 5, wherein the front lens group has a negative refractive power.

7. The optical module according to claim 1, satisfying the following conditional expression. 0.20 < Dst_im / TL1 < 0.50 however, Dst_im: Length from the aperture diaphragm to the image plane in the first optical system. TL1: The length along the optical axis from the lens surface closest to the object to the image plane of the front lens group in the first optical system.

8. An optical module having a branching surface that transmits a portion of the incident light and reflects at least a portion of the incident light that is different from the aforementioned portion, and which images the light transmitted by the branching surface and the light reflected by the branching surface, The first optical system comprises, in order from the object side, a front lens group, an optical path branching member having the branching surface, and a first rear lens group having positive refractive power into which light transmitted through the branching surface is incident. The second optical system comprises, in order from the object side, the front lens group, the optical path branching member, and a second rear lens group having positive refractive power into which light reflected at the branching surface is incident. The aforementioned front lens group has a negative lens closest to the object and a positive lens closest to the image plane. The aforementioned front lens group is an optical module having negative refractive power.

9. An optical module according to any one of claims 1, 3, 5, and 8, satisfying the following conditional expression. 0.30 < f1R / f2R < 3.33 however, f1R: Focal length of the first rear lens group f2R: Focal length of the second rear lens group

10. The optical module according to any one of claims 1, 3, 5, and 8, wherein the image formed by light from one of the first optical system and the second optical system is used to detect the appearance of the object represented in the image, and the image formed by light from the other optical system is used to detect the distance to the object represented in the image.

11. The optical module according to claim 10, wherein the F-number of the optical system used for detecting the distance to the object among the first optical system and the second optical system is less than or equal to the F-number of the optical system used for detecting the appearance of the object among the first optical system and the second optical system.

12. The optical module according to claim 11, satisfying both of the following conditions. 0.20 < Fno_tof / Fno_img < 1.00 1.00 < Fno_tof < 2.00 however, Fno_tof: The F-number of the optical system used for detecting the distance to the object, among the first and second optical systems. Fno_img: The F-number of the optical system used for detecting the appearance of the object, among the first and second optical systems.

13. The optical module according to claim 10, wherein the optical system used for detecting the appearance of the object among the first optical system and the second optical system has a cemented lens, and the optical system used for detecting the distance to the object among the first optical system and the second optical system consists of only a single lens.

14. The optical module according to claim 10, further comprising an illumination unit that emits light used for detecting the distance to the aforementioned object.

15. The optical module according to any one of claims 1, 3, 5, and 8, further comprising a first imaging unit that receives light imaged by the first optical system and a second imaging unit that receives light imaged by the second optical system, wherein one of the first imaging unit and the second imaging unit detects visible light and the other detects near-infrared light.

16. The optical module according to any one of claims 1, 3, 5, and 8, wherein the branching surface transmits light of a first wavelength included in visible light and light of a second wavelength included in near-infrared light, and reflects the other light.

17. The optical module according to any one of claims 1, 3, 5, and 8, wherein the optical path branching member has a prism, one surface of the prism is configured as the branching surface, and the prism has a total reflection surface that totally reflects at least the light on the optical axis from the light reflected at the branching surface after passing through the front lens group.

18. An optical module according to any one of claims 1, 3, 5, and 8, satisfying the following conditional expression. 1.00 < Pr1 / f1 < 6.00 however, Pr1: The length along the optical axis from the object-side surface of the optical path branching member to the image-side surface of the optical path branching member in the first optical system. f1: Focal length of the first optical system

19. An optical module according to any one of claims 1, 3, 5, and 8, satisfying the following conditional expression. 0.83 < θ1 / θ2 < 1.20 however, θ1: Total field of view of the first optical system θ2: Total field of view of the second optical system.

20. An optical module according to any one of claims 1, 3, 5, and 8, satisfying the following conditional expression. 70.0° < θ1 however, θ1: Total field of view of the first optical system

21. An optical device having an optical module according to any one of claims 1, 3, 5, and 8, for detecting the appearance of an object represented by an image formed by light imaged by the optical module and the distance to the object.

22. An optical module according to any one of claims 1, 3, 5, and 8, A detection unit that detects the appearance of an object represented by an image formed by light from the optical module and the distance to the object, respectively. A model generation unit generates shape model information indicating the shape of the object based on the distance to the detected object, A texture generation unit generates texture information representing the appearance of the object based on the appearance of the detected object, and associates the generated texture information with the shape model information. An optical device equipped with the following features.

Images