Optical lens inspection device and optical lens inspection method

Abstract

To provide an optical lens inspection device and an optical lens inspection method in which detection accuracy of almost linear flaw or the like in the same direction as the direction of irradiation light difficult to be detected is improved.SOLUTION: An optical lens inspection device 100 inspects an optical lens 1. The optical lens inspection device 100 includes: an imaging part 2 which images the optical lens 1; an illuminating member 3 which is arranged so as to be opposed to the imaging part 2 with the optical lens 1 interposed therebetween and linearly arranged so as to irradiate the optical lens 1 with light; and a first rotating part 41 which relatively rotates the illuminating member 3 with respect to the optical lens 1 approximately centered on the optical axis O1 of the optical lens 1.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The technology disclosed in this specification relates to an optical lens inspection apparatus and an optical lens inspection method. [Background technology]

[0002] Patent Document 1 proposes an apparatus for inspecting scratches and the like on optical lenses (hereinafter also simply referred to as "lenses"). The lens inspection apparatus described in Patent Document 1 includes a camera that images the lens from one side of a stage on which the lens is mounted, a line illumination means that irradiates a line of dark-field illumination inspection light from the other side of the camera across the lens, and a linear slider that can linearly move the line illumination means parallel to the stage. In Patent Document 1, the illumination device is linearly moved in a direction perpendicular to the extension direction of the line of dark-field illumination inspection light. The dark-field illumination inspection light projected from the line illumination means is irradiated onto the lens, and the dark-field illumination inspection light that has passed through the lens is received by a solid-state image sensor of the imaging device. As the illumination device moves, dark-field regions are continuously extracted in synchronization with the movement, and the dark-field regions are synthesized to generate a dark-field image of the entire lens. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-212353 A Summary of the Invention [Problem to be solved by the invention]

[0004] In such a device described in Patent Document 1, in the image of the dark field region used for inspection, the angle of light irradiation on the lens is always inclined at a predetermined angle with respect to the linear direction in which the illumination device moves. When a linear scratch or the like occurs on the lens and the direction of light irradiation is the same as the direction in which the approximately linear scratch or the like occurs on the lens, the light scattering phenomenon that occurs when the dark field illumination inspection light collides with the scratch or the like on the lens is unlikely to occur. Therefore, in such a case, the scattered light intensity is not sufficient, and it may not be possible to detect the location where an abnormality has occurred. For this reason, the device described in Patent Document 1 has a problem in that it is difficult to detect scratches or the like depending on the direction in which the approximately linear scratch or the like extends.

[0005] The technology disclosed in the present specification has been made in consideration of the problems described above. This technology relates to an optical lens inspection device and an optical lens inspection method that can easily detect scratches and the like. [Means for solving the problem]

[0007] The present invention relates to an optical lens inspection apparatus. 1 The aspect of the present invention is an apparatus for inspecting an optical lens, the apparatus including: an imaging unit that images the optical lens; an illumination member having a linear or curved shape that is disposed opposite the imaging unit across the optical lens and that irradiates the optical lens with light; and a first rotation unit that rotates the illumination member relatively to the optical lens substantially around the optical axis of the optical lens. ,before a moving mechanism for moving the illumination member relative to the optical lens between a position approaching the optical axis and a position away from the optical axis; And, Preparation The moving mechanism includes a second rotating unit that rotates the illumination member relatively to the optical lens about an axis that is located on a principal plane of the optical lens and includes a center of the optical lens. .

[0010] The present invention relates to an optical lens inspection apparatus. 2 The embodiment of the present invention is as follows: An apparatus for inspecting an optical lens, comprising: an imaging unit that images the optical lens; an illumination member having a linear or curved shape that is disposed opposite the imaging unit across the optical lens and that irradiates the optical lens with light; a first rotation unit that rotates the illumination member relatively to the optical lens substantially around an optical axis of the optical lens; and a movement mechanism that moves the illumination member relatively to the optical lens between a position approaching the optical axis and a position away from the optical axis. An illumination angle changing unit that changes the illumination direction of the light from the illumination member And, Prepare.

[0011] The present invention relates to an optical lens inspection apparatus. 3The first aspect is or the second In the optical lens inspection device of the aspect, the illumination member moves within a range such that bright field light from the illumination member does not enter the imaging unit.

[0012] The present invention relates to an optical lens inspection apparatus. 4 The embodiment is 3 In the optical lens inspection device of this aspect, the illumination member moves within a range in which bright field light from the illumination member does not enter the imaging unit and within a range in which the illumination member is not imaged by the imaging unit when a sample optical lens having the same shape as the optical lens is imaged in advance.

[0013] The present invention relates to an optical lens inspection apparatus. 5 The embodiment is the first embodiment to the third embodiment. 4 In the optical lens inspection device of the aspect, the illumination members are arranged in a line, and the width of the line along which the illumination members are arranged is approximately the same as or larger than the diameter of the optical lens.

[0014] The present invention relates to an optical lens inspection apparatus. 6 The embodiment is the first embodiment to the third embodiment. 5 In the optical lens inspection apparatus of the aspect, a control unit is further provided that judges the quality of the optical lens based on the image captured by the imaging unit.

[0015] A first aspect of an optical lens inspection method disclosed in the present specification is a method for inspecting an optical lens, the method including: a first imaging step of imaging the optical lens with an imaging unit disposed opposite the illumination member across the optical lens while irradiating the optical lens with light from an illumination member having a linear shape or a curved shape along a convex surface or a concave surface of the optical lens; a rotation step of rotating the illumination member relatively to the optical lens substantially around an optical axis of the optical lens to arrange the optical lens and the illumination member in a positional relationship different from that in the first imaging step; and a second imaging step of imaging the optical lens with the imaging unit while irradiating the optical lens with light from the illumination member after the rotation step. The method further includes a step of rotating the illumination member relatively to the optical lens about an axis that is located on a principal plane of the optical lens and includes a center of the optical lens.. A second aspect of the optical lens inspection method disclosed in the present specification is a method for inspecting an optical lens, comprising: a first imaging step of imaging the optical lens with an imaging unit arranged opposite the illumination member across the optical lens while irradiating the optical lens with light from an illumination member having a straight line or a curved line along the convex or concave surface of the optical lens; a rotation step of rotating the illumination member relatively to the optical lens approximately around the optical axis of the optical lens to place the optical lens and the illumination member in a positional relationship different from that in the first imaging step; and a second imaging step of imaging the optical lens with the imaging unit while irradiating the optical lens with light from the illumination member after the rotation step, further including a step of changing the irradiation direction of the light from the illumination member.

[0016] The present invention relates to a method for inspecting an optical lens. 3 The embodiment is 2 In the optical lens inspection method of the embodiment, the method further includes a sample imaging step of illuminating a sample optical lens having the same shape as the optical lens with the illumination member in a plurality of positional relationships in which the relative position of the sample optical lens and the illumination member is different, while imaging the sample optical lens with the imaging unit, and the relative positional relationship of the illumination member with respect to the sample optical lens and the imaging unit when an image in which no bright field light from the illumination member enters is captured in the sample imaging step is adopted as the relative positional relationship of the illumination member with respect to the optical lens and the imaging unit in the first imaging step and the second imaging step. Effect of the Invention

[0017] The first to fourth optical lens inspection apparatuses disclosed in the present specification 6 and the first to third aspects of the optical lens inspection method 3 According to this aspect, scratches and the like can be easily detected.

[0018] Objects, features, aspects and advantages associated with the technology disclosed herein will become more apparent from the detailed description set forth below and the accompanying drawings. [Brief description of the drawings]

[0019] [Figure 1] 1 is a block diagram showing an overall configuration of an inspection system including an optical lens inspection apparatus according to a first embodiment. [Diagram 2] 1 is a schematic diagram showing an overall configuration of an optical lens inspection device according to a first embodiment. [Diagram 3] FIG. 2 is a schematic explanatory diagram showing the operation of a moving mechanism of the optical lens inspection device according to the first embodiment together with the overall configuration. [Figure 4] 3A and 3B are explanatory diagrams showing examples of the configuration of a light source of an illumination member. [Diagram 5] FIG. 2 is a schematic diagram showing a moving mechanism. [Figure 6] 3 is a schematic diagram showing a moving mechanism and an optical lens. FIG. [Figure 7] 2 is a block diagram showing the connection relationship between a control unit provided in a computer and each component of the optical lens inspection apparatus. FIG. [Figure 8] FIG. 4 is a plan view showing the positional relationship between an optical lens and an illumination member. [Figure 9] 13 is a plan view showing the positional relationship between the optical lens and the illumination member after the illumination member has been rotated by a first rotating portion. FIG. [Figure 10] FIG. 2 is a flow diagram showing a process of inspecting an optical lens by the optical lens inspection apparatus according to the first embodiment. [Figure 11] 2 is a diagram showing the positional relationship between an imaging device, an optical lens, and an illumination member in a coordinate system. [Figure 12] 13 is a schematic explanatory diagram showing the operation of a moving mechanism of an optical lens inspection apparatus according to a second embodiment together with the overall configuration. FIG. [Figure 13] FIG. 12 is a schematic diagram showing the movement mechanism shown in FIG. [Figure 14] FIG. 11 is a flow chart showing steps for determining a range in which an illumination member is moved by the optical lens inspection apparatus according to the third embodiment. [Figure 15] 4 is an explanatory diagram showing a path of irradiation light from an illumination member to an imaging unit. FIG. [Figure 16] 4 is an explanatory diagram showing a path of irradiation light from an illumination member to an imaging unit. FIG. [Figure 17] 4 is an explanatory diagram showing a path of irradiation light from an illumination member to an imaging unit. FIG. [Figure 18] 4 is an explanatory diagram showing a path of irradiation light from an illumination member to an imaging unit. FIG. [Figure 19] 4 is an explanatory diagram showing a path of irradiation light from an illumination member to an imaging unit. FIG. [Figure 20] 4 is an explanatory diagram showing a path of irradiation light from an illumination member to an imaging unit. FIG. [Figure 21]13A and 13B are diagrams illustrating a preferred arrangement of illumination members for clearly determining whether or not there is a defect in an optical lens. [Figure 22] FIG. 11 is a plan view showing the arrangement of illumination members that prevent the bright field region from being reflected. [Diagram 23] 1 is an explanatory diagram showing an optical lens and illumination members arranged in a curved line; [Figure 24] FIG. 11 is a side view showing an illumination member and a moving mechanism in a modified example of the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, the embodiments will be described with reference to the accompanying drawings. In the following embodiments, detailed features are shown for the purpose of explaining the technology, but they are merely examples and are not necessarily essential features for enabling the embodiments to be implemented.

[0021] The drawings are shown in a schematic manner, and for the convenience of explanation, configurations are omitted or simplified as appropriate in the drawings. Furthermore, the size and positional relationship of the configurations shown in different drawings are not necessarily described accurately, and may be changed as appropriate. Furthermore, hatching may be added to drawings such as plan views that are not cross-sectional views in order to make it easier to understand the contents of the embodiment.

[0022] In the following description, similar components are denoted by the same reference numerals in the drawings, and their names and functions are also similar. Therefore, detailed descriptions thereof may be omitted to avoid duplication.

[0023] In the following description, when a certain component is described as "comprising," "including," or "having," unless otherwise specified, the description is not an exclusive expression that excludes the presence of other components.

[0024] In the description below, even if ordinal numbers, such as "first" and "second", are used, these terms are used for convenience to facilitate understanding of the contents of the embodiments, and the techniques described in the embodiments are not limited to the order that may result from these ordinal numbers.

[0025] In the drawings, the dimensions and numbers of each part may be exaggerated or simplified for ease of understanding. In addition, XYZ orthogonal coordinate axes (right-handed system) are appropriately attached to each drawing to explain the directions. The Z direction in the coordinate axes indicates the vertical direction, and the XY plane is a horizontal plane. Hereinafter, one side of the X direction may be referred to as the +X side, and the opposite side as the -X side. The same applies to the Y axis and the Z axis, and the +Z side indicates the vertically upward side.

[0026] <First embodiment> The optical lens inspection apparatus 100 according to the first embodiment will be described below.

[0027] <Configuration of Optical Lens Inspection Apparatus 100> 1 is a block diagram showing the overall configuration of an inspection system 101. The inspection system 101 includes an optical lens inspection apparatus 100 according to the present embodiment. The inspection system 101 includes a storage unit 102, a good product storage unit 103, and a defective product storage unit 104. The storage unit 102 stores optical lenses to be inspected. The good product storage unit 103 receives and stores optical lenses that have been determined to be good products by the optical lens inspection apparatus 100. The defective product storage unit 104 receives and stores optical lenses that have been determined to be defective products by the optical lens inspection apparatus 100.

[0028] The inspection system 101 further includes transfer mechanisms 105, 106, and 107. The transfer mechanism 105 transfers optical lenses between the storage section 102 and the optical lens inspection device 100. The transfer mechanism 106 transfers optical lenses between the optical lens inspection device 100 and the non-defective product storage section 103. The transfer mechanism 107 transfers optical lenses between the optical lens inspection device 100 and the defective product storage section 104. The arrows in the figure indicate the direction in which the optical lenses are transferred. Note that the transfer mechanisms 106 and 107 may be configured by the same mechanism, or may be shared.

[0029] The inspection system 101 is connected to a control unit 50, which will be described in detail later. The control unit 50 controls each device to process the optical lens.

[0030] Fig. 2 is a schematic diagram showing the overall configuration of an optical lens inspection device 100 according to this embodiment. Fig. 3 is a schematic explanatory diagram showing the operation of a movement mechanism 4 of the optical lens inspection device 100 according to this embodiment together with the overall configuration. The optical lens inspection device 100 includes an imaging unit 2 that images an optical lens 1 to be inspected, an illumination member 3 that irradiates the optical lens 1 with light, and a movement mechanism 4 that moves the illumination member 3.

[0031] The optical lens inspection apparatus 100 is connected to a computer 5. The computer 5 has a function of a control unit 50 that controls the overall operation of the inspection system 101. The control unit 50 controls the overall operation of the optical lens inspection apparatus 100.

[0032] The optical lens 1 is held by an optical lens holding part (not shown) and fixed to the optical lens inspection device 100. The optical lens holding part is composed of, for example, a plate-like member having a hollow hole formed therein. The optical lens 1 is fixed to the optical lens inspection device 100 by holding the peripheral part of the optical lens 1 in this hollow hole.

[0033] The imaging unit 2 has an optical system 21 and an imaging device 22. The optical system 21 includes an imaging lens 23. The imaging lens 23 guides light from the illumination member 3 that passes through the optical lens 1 to the imaging device 22 to form an image. The optical system 21 further includes an aperture stop 24. The aperture stop 24 functions as a shield that adjusts the amount of light that passes through the optical lens 1 and reaches the imaging device 22. The imaging device 22 is, for example, a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor.

[0034] 7 is a block diagram showing the connection relationship between the control unit 50 and each component of the optical lens inspection device 100. For example, the control unit 50 includes a CPU (central processing unit) 51, which is a central processing unit that performs various arithmetic processing, a ROM (read only memory) 52, which is a read only memory that stores a basic program, and a RAM (random access memory) 53, which is a readable and writable memory that stores various information. The CPU 51 is connected to the illumination member 3, the moving mechanism 4, the imaging unit 2, etc., and the control unit 50 controls these. The control unit 50 also stores the image captured by the imaging unit 2 in the RAM 53. The image stored in the RAM 53 is processed by the CPU 51. The control unit 50 is realized by, for example, a computer 5.

[0035] Fig. 4 is an explanatory diagram showing an example of the configuration of the light source of the illumination member 3. The illumination member 3 is disposed facing the imaging unit 2 with the optical lens 1 interposed therebetween. The illumination member 3 has a plurality of light sources 33 as shown in Fig. 4. These light sources 33 are arranged, for example, in a line. The illumination member 3 may be configured by a plurality of LEDs (Light Emitting Diodes) arranged in a line, a linear halogen lamp, a plurality of halogen lamps arranged in a line, or a plurality of laser light sources arranged in a line.

[0036] The illumination member 3 is fixed to the moving mechanism 4 and moves with the movement of the moving mechanism 4. Fig. 5 is a schematic diagram showing the moving mechanism 4, and Fig. 6 is a schematic diagram showing the moving mechanism 4 and the optical lens 1. Fig. 5 shows a rotation direction 41R of a first rotating part 41 constituting the moving mechanism 4. Fig. 6 shows a rotation direction 42S of a second rotating part 42 constituting the moving mechanism 4.

[0037] The moving mechanism 4 includes a first rotating unit 41 and a second rotating unit 42 attached to the first rotating unit 41. The illumination member 3 is fixed to the second rotating unit 42 such that the irradiation direction of the light source 33 faces the optical lens 1. The first rotating unit 41 rotates the illumination member 3 relative to the optical lens 1 via the second rotating unit 42, approximately about the optical axis O1 of the optical lens 1.

[0038] The second rotating unit 42 is configured by, for example, a goniostage. The goniostage includes a guide rail 42a and a moving member 42b that moves on the guide rail 42a. The guide rail 42a is fixed to the first rotating unit 41 on the first rotating unit 41 side. On the opposite side to the first rotating unit 41, the moving member 42b rotates on the guide rail 42a with an axis O2 as a substantial center. The axis O2 is located on the principal plane P1 of the optical lens 1 and includes the center C of the optical lens 1. The moving member 42b is disposed on the guide rail 42a. The guide rail 42a guides the moving member 42b so that the moving member 42b moves back and forth in the rotation direction 42S. As the moving member 42b moves in the rotation direction 42S, the illumination member 3 moves along the rotation direction 42S. In this way, the second rotating unit 42 moves the illumination member 3 between a position approaching the optical axis O1 and a position away from the optical axis O1 relative to the optical lens 1. Then, for example, the second rotating unit 42 moves the illumination member 3 so that the angle between the optical axis O1 and a line connecting the illumination member 3 and the axis O2 changes.

[0039] With the above-described configuration, when the first rotating unit 41 rotates around the optical axis O1, the second rotating unit 42 also rotates around the optical axis O1 in accordance with the rotation of the first rotating unit 41. This causes the illumination member 3 fixed to the second rotating unit 42 to also rotate. The irradiation direction 3D of light from the illumination member 3 to the optical lens 1 is changed in accordance with the movement of the moving member 42b on the guide rail 42a. In other words, the irradiation direction 3D of light from the illumination member 3 to the optical lens 1 is changed according to the illumination angle θ (the illumination angle θ is set to 0 degrees when the irradiation direction 3D coincides with the optical axis O1) at which the illumination member 3 moves on the goniostage (guide rail 42a).

[0040] FIG. 8 is a plan view showing the positional relationship between the optical lens 1 and the illumination member 3. The width d of the linear arrangement of the multiple light sources 33 in the illumination member 3 is, for example, approximately the same as the diameter 2R of the optical lens 1 or is greater than the diameter 2R. In this way, if d≧2R, the illumination member 3 is scanned once in the direction of the arrow S in FIG. 8, and the illumination member 3 illuminates approximately the entire surface of the optical lens 1. However, even if d<2R, the illumination member 3 also moves in a direction perpendicular to the direction of the arrow S in the XY plane direction in FIG. 7, and the illumination member 3 illuminates approximately the entire surface of the optical lens 1. The image processing performed by the CPU 51 is performed, for example, by using a dark field region 31 extracted from an image captured by the imaging unit 2. The dark field region 31 is a region that exists at the boundary between a bright part and a dark part. Here, the bright part refers to the bright field region 32, and the dark part refers to a region where light does not reach from the illumination member 3. The dark field region 31 is a region obtained by excluding the bright field region 32 from the entire region illuminated by light. The bright field region 32 refers to a region obtained only from the bright field light from the illumination member 3 .

[0041] The dark field region 31 is extracted, for example, by masking the bright field region 32. An image of only the extracted dark field region 31 is obtained. The reason for extracting only the dark field region 31 is to enhance contrast and facilitate detection of fine scratches. The illumination member 3 is moved in the direction of the arrow S by the second rotating unit 42, and a predetermined region of the optical lens 1 is imaged. A dark field image, which is an image of only the dark field region 31 obtained by this imaging, is created by the control unit 50. The quality of the optical lens 1 is determined based on this dark field image. The predetermined region is, for example, a region that is determined by giving priority to a location on the optical lens 1 that is likely to have scratches.

[0042] FIG. 9 is a plan view showing the positional relationship between two positions of the illumination member 3 obtained by rotating the illumination member 3 by the first rotating unit 41 and the optical lens 1. In this embodiment, the first rotating unit 41 changes the direction of the axis O2 of the second rotating unit 42 of the illumination member 3 on the XY plane. Specifically, the illumination member 3 irradiates a predetermined area of ​​the optical lens 1 by the rotation of the second rotating unit 42 at the initial position of the first rotating unit 41, and then rotates by a predetermined angle β around the optical axis O1 by the first rotating unit 41. This predetermined angle β is, for example, 45 degrees around the optical axis O1. In this way, when the illumination member 3 is rotated by the first rotating unit 41, the optical lens 1 is irradiated from a plurality of angles (a plurality of positions) by the illumination member 3. Also, when the illumination member 3 is rotated by the first rotating unit 41, the optical lens 1 is irradiated from a plurality of irradiation directions 3D.

[0043] 9, in the initial position of the first rotating unit 41, the axis O2 is parallel to the X direction, and the illumination member 3 (including the dark field region 31 and the bright field region 32) at this time is indicated by a dashed line. The illumination member 3 (including the dark field region 31 and the bright field region 32) after the first rotating unit 41 has rotated by a predetermined angle β from the initial position is indicated by a solid line and a dashed line. Note that the dark field region 31 and the bright field region 32 indicated by the dashed lines are shown in their states before passing through the optical lens 1.

[0044] Here, for example, when light is irradiated from a direction parallel to the extension direction of the defect 11 (at an angle of 0 degrees or 180 degrees) to the defect 11 caused by a streak-like (straight line) scratch, the light scattering phenomenon due to the scratch is unlikely to occur. Therefore, sufficient contrast may not be obtained between the scratch and the non-scratched portion in the captured image. Therefore, the scratch may not be detected. In contrast, when light is irradiated from an angled direction (at an angle other than 0 degrees and 180 degrees) to the defect 11 caused by a streak-like (straight line) scratch, the light scattering phenomenon due to the scratch is likely to occur. Therefore, the contrast between the defect 11 caused by the scratch and the non-defected portion in the captured image is improved. According to this optical lens inspection device 100, the irradiation direction 3D can be set to multiple directions, making it easy to detect linear scratches that have been overlooked in the past.

[0045] In this embodiment, a transparent optical lens 1 is exemplified as an inspection target. If the transparent optical lens 1 has a defect 11 such as a scratch, the light from the illumination member 3 is scattered by the defect 11. Since the size of the defect 11 is generally larger than the wavelength of light, when the defect 11 is irradiated with light, a so-called Mie scattering phenomenon (a scattering phenomenon of light by spherical particles having a size equal to or larger than the wavelength of light) occurs. A part of the light scattered by this Mie scattering phenomenon (hereinafter referred to as "scattered light") is captured by the imaging unit 2, and the control unit 50 processes the image, thereby detecting the defect 11. Note that the image processing by the control unit 50 is performed, for example, by binarization processing. In the binarized image, for example, bright parts are processed as "H" and dark parts are processed as "L". If scattered light is reflected, the part where the scattered light is reflected becomes bright, and the part is processed as "H". Conversely, the part where the light is not reflected becomes dark, and the part is processed as "L". Therefore, for example, if a portion of the image being processed that contains scattered light is processed as "H", the control unit 50 will determine that the optical lens 1 is defective. On the other hand, if there is no portion that contains scattered light, the entire image will be processed as "L", and the control unit 50 will determine that the optical lens 1 is good.

[0046] <Inspection process by the optical lens inspection device 100 according to the first embodiment> 10 is a flow diagram showing the process of inspecting the optical lens 1 by the optical lens inspection device 100 according to the first embodiment. When the optical lens 1 is inspected by the optical lens inspection device 100, first, irradiation of the optical lens 1 with light from the illumination member 3 is started (step S1).

[0047] After irradiation of the optical lens 1 with light from the illumination member 3 starts in step S1, the second rotation unit 42 rotates (step S2). The second rotation unit 42 rotates manually or automatically. In the case of automatic rotation, it is controlled by the control unit 50. In this embodiment, the second rotation unit 42 is configured by a goniostage. The relationship between the trajectory of the illumination member 3 rotated by this goniostage and the irradiation position from the illumination member 3 on the principal plane P1 of the optical lens 1 can be found as follows.

[0048] 11 is a diagram showing, in a coordinate system, the positional relationship between the imaging device 22, the optical lens 1, and the illumination member 3. In FIG. 11, the coordinates (0,0) of the center C of the optical lens 1, the coordinates (y0,0) of the position D where the illumination member 3 illuminates the principal plane P1 of the optical lens 1, and the inclination θ of the line connecting the center E of the imaging lens 23 of the imaging unit 2 with respect to the optical axis O1 of the optical lens 1 are (y0,0). I , the coordinates of the position F of the lighting member 3 (y s ,z s ), the radius r of the arc J that represents the range that position F can take, the inclination θ0 of the line L that connects positions D and F with respect to the optical axis O1, and the illumination angle θ between the line K that connects center C and position F and the optical axis O1 are introduced, and the following quantities are obtained. Note that the center C of the optical lens 1 may be regarded as the center of a circle formed by the principal plane P1 of the optical lens 1.

[0049] The tilt θ0 is the power of the optical lens 1 (= focal length f L The reciprocal of this is expressed by the following formula (1).

[0050]

number

[0051] Moreover, the line connecting the positions D and F is expressed by the following formula (2), and the arc J is expressed by the following formula (3).

[0052]

number

[0053]

number

[0054] Position F is the intersection of arc J and line L. Among the coordinates (y, z) that satisfy both equation (2) and equation (3), the one that meets the condition z<0 is the coordinate (y s ,z s ) is valid. y = y s, z=z s are expressed by the following formulas (4) and (5), respectively.

[0055]

number

[0056]

number

[0057] The illumination angle θ satisfies the following formula (6).

[0058]

number

[0059] By substituting equations (4) and (5) into equation (6), we obtain the following equation (7).

[0060]

number

[0061] Using equation (7), the illumination angle θ when the light from the illumination member 3 illuminates the position D on the optical lens 1, passes through the center E of the imaging lens, and is incident on the imaging element surface is calculated. I That is, it is possible to obtain the illumination angle θ when capturing a bright field image of the position D. This allows the movable range of the illumination angle θ with respect to the center position C of the optical lens 1 to be obtained.

[0062] By executing step S2, the illumination member 3 rotates around the axis O2 in accordance with the rotation of the second rotating unit 42. A predetermined area of ​​the optical lens 1 (a predetermined area, for example, the entire area of ​​the optical lens 1 imaged by the imaging unit 2) is irradiated by the rotation of the illumination member 3. In step S3, it is determined whether the rotation of the second rotating unit 42 has ended. If it is determined that the rotation has ended, the imaging unit 2 images the optical lens 1 while maintaining the light irradiation (step S4). In this way, the optical lens inspection device 100 images the optical lens 1 by the imaging unit 2 arranged opposite the illumination member 3 across the optical lens 1 while irradiating the optical lens 1 with light from the illumination member 3 (first imaging step). When the optical lens 1 is imaged, the optical lens 1 is focused. Thereafter, the process proceeds to step S5. If it is determined that the rotation has not ended in step S3, the process returns to step S2 and the second rotating unit 42 is rotated.

[0063] In step S5, the control unit 50 processes the image captured by the imaging unit 2. As described above, this image processing is performed by extracting only the dark-field region 31. The control unit 50 forms a dark-field image using only the image of the extracted dark-field region 31. In step S6, the control unit 50 determines whether the dark-field image contains scattered light due to the defect 11 in the optical lens 1 (step S6).

[0064] If it is determined in step S6 that the scattered light is not included in the dark-field image, the optical lens 1 is determined to be good (step S7). If it is determined in step S6 that the scattered light is included in the dark-field image, the optical lens 1 is determined to be defective (step S8).

[0065] If the optical lens 1 is determined to be good in step S7, it is determined whether or not the first rotating unit 41 needs to rotate (step S9). This is because a scratch that forms a small angle with the projection onto P1 of the irradiation direction 3D of the light from the illumination member 3 is difficult to detect only by scanning the optical lens 1 with the second rotating unit 42. For this reason, in this embodiment, after step S11 is executed and the first rotating unit 41 rotates, the process returns to step S3 again. The angle by which the first rotating unit 41 rotates in step S11 is, for example, 45 degrees around the optical axis O1. After the rotation of the first rotating unit 41, the second rotating unit 42 rotates again in step S3, so that the illumination member 3 changes the direction of projection onto P1 of the irradiation direction 3D. As a result, according to the optical lens inspection device 100 of this embodiment, even a streak-like (straight-line) scratch on the optical lens 1 is easily detected.

[0066] If the first rotating unit 41 has already rotated and the illumination member 3 has irradiated the optical lens 1 with light by changing the direction of projection onto P1 of the irradiation direction 3D, it is determined in step S9 that rotation of the first rotating unit 41 is not necessary. Then, the optical lens 1 is determined to be good (step S10), and the inspection of the optical lens 1 by the optical lens inspection device 100 is completed. On the other hand, if further illumination from another angle is required for the optical lens 1, it is determined in step S9 that rotation of the first rotating unit 41 is necessary. If it is determined in step S9 that rotation of the first rotating unit 41 is necessary, the first rotating unit 41 rotates (step S11) (rotation process). The optical lens inspection device 100 rotates the illumination member 3 relative to the optical lens 1, approximately centered on the optical axis O1 of the optical lens 1. Then, the optical lens inspection device 100 places the optical lens 1 and the illumination member 3 in a positional relationship different from that in the first imaging process. After the first rotating unit 41 has rotated, the process returns to step S2 again, and after the rotation step of step S11, the optical lens inspection device 100 rotates the second rotating unit 42 and captures an image of the optical lens 1 by the imaging unit 2 while irradiating the optical lens 1 with light from the illumination member 3 (second imaging step). Then, inspection of the optical lens 1 is performed.

[0067] <Second embodiment> An optical lens inspection apparatus 200 according to the second embodiment will be described below.

[0068] <Configuration of Optical Lens Inspection Apparatus 200> Fig. 12 is a schematic explanatory diagram showing the operation of a moving mechanism 240 of an optical lens inspection device 200 according to the second embodiment together with the overall configuration. The optical lens inspection device 200 of the second embodiment includes a moving mechanism 240. The moving mechanism 240 includes a first rotating unit 41 and a planar moving unit 242 fixed to the first rotating unit 41. Fig. 13 is a schematic diagram showing the moving mechanism 240 of Fig. 12. Fig. 12 shows a rotation direction 41R of the first rotating unit 41 and a moving direction 242S of the planar moving unit 242 that configure the moving mechanism 240.

[0069] The planar moving section 242 moves the illumination member 3 on a plane (XY plane) perpendicular to the optical axis O1. The planar moving section 242 includes a guide rail 242a and a moving member 242b that moves on the guide rail 242a. The guide rail 242a is fixed to the first rotating section 41. The guide rail 242a guides the moving member 242b so that the moving member 242b moves back and forth in a linear moving direction 242S on the XY plane. The illumination member 3 is fixed to the moving member 242b and moves with the movement of the moving member 242b. With the movement of the moving member 242b in the moving direction 242S, the illumination member 3 moves in the 242S direction. In this way, the planar moving section 242 moves the illumination member 3 between a position approaching the optical axis O1 and a position away from the optical axis O1.

[0070] Among the inspection steps by the optical lens inspection device 100, the rotational movement of the illumination member 3 by the second rotation unit 42 in step S3 is changed to the linear movement of the illumination member 3 by the planar movement unit 242, and the inspection steps by the optical lens inspection device 200 are obtained. That is, in the second embodiment, the position F of the illumination member 3 moves not on the arc J but on a straight line parallel to the Y axis. The illumination angle θ and the like can be calculated by replacing the formulas (1) to (10) in the first embodiment with the condition that the position F moves on a straight line of z=-r. The other points of the inspection steps by the optical lens inspection device 200 are the same as those of the inspection steps by the optical lens inspection device 100. The optical lens inspection device 200 employs the planar movement unit 242, and therefore can move the illumination member 3 with a simpler configuration than that of employing the second rotation unit 42. However, the configuration of the second rotation unit 42 is preferable in that the irradiation direction 3D of light from the illumination member 3 to the optical lens 1 can be easily changed with the movement of the movement member 42b.

[0071] <Third embodiment> A third embodiment of the present invention will be described below. The third embodiment uses an optical lens inspection device 100 having the same configuration as the first embodiment.

[0072] <Inspection process by the optical lens inspection device 100 according to the third embodiment> By the optical lens inspection apparatus 100 according to the third embodiment, the illumination member 3 moves within a range in which bright field light from the illumination member 3 does not enter the imaging unit 2. This range is determined in advance by imaging a sample optical lens having the same shape as the optical lens 1 to be inspected. Fig. 14 is a flow diagram showing the process of determining the range in which the illumination member 3 moves by the optical lens inspection apparatus 100 according to the third embodiment.

[0073] An optical lens inspection device 100 according to the third embodiment illuminates a sample optical lens having the same shape as an optical lens 1 from a plurality of positions that are different relative to the sample optical lens using an illumination member 3. Then, this optical lens inspection device 100 images the sample optical lens using an imaging unit 2 that faces the illumination member 3 with the sample optical lens in between.

[0074] Specifically, before the optical lens 1 is inspected by the optical lens inspection apparatus 100, a sample optical lens having the same shape as the optical lens 1 is inspected. First, light is irradiated from the illumination member 3 to the sample optical lens set in the optical lens inspection apparatus 100 (step S101). A lens having the same shape as the optical lens 1 to be actually inspected is adopted as the sample optical lens. When the illumination member 3 starts irradiating light in step S101, the imaging unit 2 starts imaging the sample optical lens (step S102).

[0075] After the illumination member 3 starts irradiating the sample optical lens with light in step S101, the second rotating unit 42 rotates (step S102).

[0076] By executing step S102, the illumination member 3 rotates around the axis O2 in accordance with the rotation of the second rotation unit 42. A predetermined area (a predetermined area, for example, the entire area of ​​the optical lens 1 imaged by the imaging unit 2) of the sample optical lens is irradiated by the rotation of the illumination member 3. In step S103, it is determined whether the rotation of the second rotation unit 42 has ended. If it is determined that the rotation has ended, the imaging unit 2 images the sample optical lens (step S104). At this time, the optical lens inspection device 100 images the sample optical lens by the imaging unit 2 while illuminating the sample optical lens by the illumination member 3 (sample imaging step). Thereafter, the process proceeds to step S105. Note that if it is determined in step S103 that the rotation has not ended, the process returns to step S102 and the rotation of the second rotation unit 42 continues. The determination of whether the first rotation unit 41 needs to rotate is necessary for the same reason as in the case of the optical lens 1 in the first embodiment.

[0077] As in the case of the optical lens 1 in the first embodiment, it is determined whether or not the first rotating unit 41 needs to rotate (step S105). If it is determined in step S105 that the first rotating unit 41 needs to rotate, the first rotating unit 41 is rotated and rotates (step S106). In this way, the optical lens inspection device 100 illuminates the sample optical lens with the illumination member 3 in a plurality of positional relationships in which the relative positions of the sample optical lens and the illumination member 3 are different. The first rotating unit 41 is rotated more times than the first rotating unit 41 is rotated when the optical lens 1 to be imaged later is imaged. This is because it is preferable that the dark field region 31 and the bright field region 32 in the optical lens 1 are grasped in advance. After the first rotating unit 41 rotates, the process returns to step S102 again. By repeating these operations, the range in which the dark field region is obtained in the optical lens 1 to be imaged later is grasped.

[0078] If the first rotating part 41 has already rotated and the illumination member 3 has changed the direction of projection onto P1 of the irradiation direction 3D to irradiate light onto the optical lens 1, it is determined in step S105 that rotation of the first rotating part 41 is not necessary.

[0079] When the rotation of the first rotating unit 41 and the rotation of the second rotating unit 42 are completed, in step S107, the image captured by the imaging unit 2 is processed by the control unit 50. By processing this image, it is determined whether or not the bright field region 32 is reflected in the captured image.

[0080] Here, the cases where the bright field region 32 is reflected in the captured image and where it is not reflected will be described with reference to the drawings. Figs. 15 to 20 are explanatory diagrams showing the path of the irradiated light from the illumination member 3 to the imaging unit 2. Figs. 15 and 16 show the case where the arrangement relationship of the illumination member 3, the optical lens 1, and the imaging unit 2 is the same. Figs. 17 and 18 show the case where the arrangement relationship of the illumination member 3, the optical lens 1, and the imaging unit 2 is the same. Figs. 19 and 20 show the case where the arrangement relationship of the illumination member 3, the optical lens 1, and the imaging unit 2 is the same. Figs. 15, 17, and 19 show the case where there is no defect 11 at the irradiation position of the light from the illumination member 3 on the optical lens 1. Figs. 16, 18, and 20 show the case where there is a defect 11 at the irradiation position of the light from the illumination member 3 on the optical lens 1.

[0081] 15 and 16 compare the paths of the light irradiated from the illumination member 3. In FIG. 15, the light irradiated from the illumination member 3 passes through the optical lens 1, the imaging lens 23, and the aperture stop 24 to reach the imaging device 22. Therefore, in the arrangement of the illumination member 3 in FIG. 15, the bright field region 32 is reflected in the captured image. In FIG. 16, a case is shown in which the light irradiated from the illumination member 3 collides with a defect 11 in the optical lens 1, causing a scattering phenomenon. The scattered light caused by this scattering phenomenon passes through the optical lens 1, the imaging lens 23, and the aperture stop 24 to reach the imaging device 22. In both FIG. 15 and FIG. 16, the light irradiated from the illumination member 3 is reflected in the captured image. Therefore, in the arrangement of the illumination member 3 shown in FIG. 15 and FIG. 16, the presence or absence of the defect 11 in the optical lens 1 is not clear.

[0082] 17 and 18 compare the paths of the irradiated light from the illumination member 3. In FIG. 17, the irradiated light from the illumination member 3 passes through the optical lens 1, but is blocked by the aperture stop 24 and does not reach the imaging device 22. Therefore, in the arrangement of the illumination member 3 in FIG. 17, the bright field region 32 is not reflected in the captured image. FIG. 18 shows a case where the irradiated light from the illumination member 3 collides with a defect 11 in the optical lens 1, causing a scattering phenomenon. A part of the scattered light caused by this scattering phenomenon passes through the optical lens 1, the imaging lens 23, and the aperture stop 24 and reaches the imaging device 22. In the arrangement of the illumination member 3 shown in FIG. 17 and FIG. 18, the light is reflected in the captured image only when the optical lens 1 has a defect 11, so the presence or absence of the defect 11 in the optical lens 1 is clear.

[0083] 19 and 20 compare the paths of the irradiated light from the illumination member 3. In FIG. 19, the irradiated light from the illumination member 3 passes through the optical lens 1, but is blocked by the aperture stop 24 and does not reach the imaging device 22. Therefore, with the arrangement of the illumination member 3 in FIG. 19, the bright field region 32 is not reflected in the captured image. FIG. 20 shows a case where the irradiated light from the illumination member 3 collides with a defect 11 in the optical lens 1, causing a scattering phenomenon. The scattered light caused by this scattering phenomenon passes through the optical lens 1 and the aperture stop 24 and reaches the imaging device 22. Therefore, with the arrangement of the illumination member 3 shown in FIG. 19 and FIG. 20, the presence or absence of a defect 11 in the optical lens 1 becomes clear.

[0084] As described above, it is understood that the positional relationship between the illumination member 3, the optical lens 1, and the imaging unit 2 is important in order to clarify the presence or absence of the defect 11 in the optical lens 1. FIG. 21 is a diagram for explaining an example of a preferable arrangement of the illumination member 3 for clarifying the presence or absence of the defect 11 in the optical lens 1. More specifically, it is a diagram showing the relationship between the irradiation angle and the detection degree when imaging is performed while changing the irradiation angle of the illumination on a sample optical lens in which the defect 11 is artificially provided at a predetermined position in advance. In FIG. 21, the illumination angle θ on the horizontal axis indicates the illumination angle θ in FIG. 5 and FIG. 10. For example, the illumination angle θ is controlled by the operation of the second rotation unit 42 (first embodiment) or the plane movement unit 242 (second embodiment). In this figure, P indicates the pixel value of the part corresponding to the defect 11 in the captured image, and P' indicates the pixel value of the part corresponding to the periphery of the defect 11 in the captured image. The portion corresponding to defect 11 and the portion corresponding to the periphery of defect 11 are distinguished by specifying in advance the pixel positions of the portion corresponding to defect 11 and the portion corresponding to the periphery of defect 11 in the captured image, based on information about the position where defect 11 was created. In FIG. 21, the range of illumination angle θ<θ1 is the region in which bright field region 32 is reflected. In this range, pixel values ​​are high overall due to the influence of bright field light. In this range, P and P' cannot be distinguished.

[0085] In FIG. 21, the detection degree P / P' shown on the vertical axis (right side) indicates [value of P] / [value of P']. Referring to FIG. 21, it can be seen that when the illumination angle θ is less than the value θ1 (≈4.5 [deg]), the detection degree P / P' is 1, and the presence or absence of the defect 11 in the optical lens 1 is not clear. In contrast, when the illumination angle θ is equal to or greater than the value θ2 (≈7.5 [deg]), the detection degree P / P' generally exceeds 1.5. When the detection degree P / P' exceeds 1.5, the defect 11 becomes clear enough to be fully grasped. Therefore, it can be seen that the presence or absence of the defect 11 in the optical lens 1 becomes clear. In particular, when the illumination angle θ is θ2<θ<16 [deg], it can be seen that the detection degree P / P' greatly exceeds 1.5, and the presence or absence of the defect 11 in the optical lens 1 becomes noticeable. In this example, it has been found by experiment that when the detection degree P / P' exceeds 1.5, bright field light from the illumination member 3 is not reflected.

[0086] Here, when the value of the illumination angle θ is less than θ1 (≈4.5 [deg]), the detection degree P / P' becomes 1 when bright field light is reflected in the image. When bright field light is reflected in this way, the scattered light due to the defect 11 becomes less noticeable due to the bright field light. Therefore, when the illumination member 3 is arranged under the condition where the detection degree P / P' becomes large (θ2<θ<16 [deg]), the difference between the defect 11 and the part that is not the defect 11 becomes clear. Therefore, the defect 11 can be detected even if the number of images taken is small. Therefore, when the detection degree becomes large, the number of images taken can be reduced, and the optical lens 1 can be inspected in a short time and at low cost. Note that θ1 and θ2 depend on the power of the optical lens 1 and the position of the defect 11, so the numerical values ​​described above (described later) are only examples. Similarly, the index value of the detection degree is set to 1.5 in the above example, but this is also only an example, and is appropriately adjusted according to the power of the optical lens 1 to be inspected and the position of the defect 11.

[0087] FIG. 22 is a plan view showing the arrangement of the illumination member 3 so that the bright field region 32 is not reflected. Specifically, a particularly preferable arrangement condition for the illumination member 3 is that the illumination member 3 is arranged such that the distance from the center C of the optical lens 1 in the XY plane view is R+w (R is the radius of the optical lens 1, and w is 1 / 2 the width (2w) of the illumination member 3). With this arrangement, the bright field region 32 is not reflected in the captured image, and the detection degree is also increased. However, the condition for this illumination angle θ depends on the power of the optical lens 1. This illumination angle θ can be calculated by setting y0=R+w in equation (7) in the first embodiment.

[0088] From the above explanation, it can be seen that whether or not the bright field region 32 is reflected in the captured image largely depends on the arrangement of the illumination member 3 and the settings of the conditions of the aperture stop 24 of the imaging section 2.

[0089] If it is determined in step S108 that the bright field region 32 is not reflected in the captured image, then in step S109, the range of movement of the illumination member 3 relative to the sample optical lens 1 is determined as the range of movement of the illumination member 3 for inspecting the optical lens 1.

[0090] If it is determined in step S108 that the bright field region 32 is reflected in the captured image, then in step S110, the range excluding the arrangement conditions of the illumination member 3 in the image in which the bright field region 32 is reflected is determined as the range of movement of the illumination member 3 in the inspection of the optical lens 1. In the above-mentioned sample imaging process, the relative positional relationship of the illumination member 3 to the sample optical lens and the imaging unit 2 when an image in which no bright field light from the illumination member 3 enters (is not reflected) is captured is adopted as the relative positional relationship of the illumination member 3 to the optical lens 1 and the imaging unit 2 in the first imaging process and the second imaging process.

[0091] In this way, the optical lens inspection device 100 according to the third embodiment inspects the optical lens 1 within a predetermined range of movement of the illumination member 3. Specifically, the optical lens 1 is inspected according to a flow similar to that in Fig. 10. The optical lens inspection device 100 illuminates the optical lens 1 with the illumination member 3 from a plurality of positions that are different relative to the optical lens 1, and captures an image with the imaging unit 2.

[0092] In the optical lens inspection device 100 of the third embodiment, the relative positional relationship between the sample optical lens of the illumination member 3 and the imaging unit 2 when an image in which no bright field light from the illumination member 3 enters (an image in which the bright field area 32 is not reflected) is captured is adopted as the relative positional relationship between the optical lens 1 of the illumination member 3 and the imaging unit 2.

[0093] In the above-described embodiment, the illumination members 3 are arranged in a straight line, but the arrangement is not limited to a straight line arrangement, and may be arranged in a curved line. FIG. 23 is an explanatory diagram showing the optical lens 1 and the illumination members 3 arranged in a curved line. As shown in FIG. 23, the light-emitting parts of the illumination members 3 are arranged in a shape (for example, a curved line) corresponding to the shape of the convex or concave surface of the optical lens 1, and the distance between each light-emitting part of the illumination member 3 and the optical lens 1 can be made substantially the same. This makes it easier to adjust the focal position of the light in the imaging unit 2 of the light irradiated from each light-emitting part through the optical lens 1. Therefore, it becomes easier to detect defects 11 in the optical lens 1.

[0094] In the above-mentioned embodiment, the optical lens 1 may rotate relatively with respect to the illumination member 3, approximately centered on the optical axis O1. Therefore, a configuration in which the optical lens 1 rotates instead of the illumination member 3 may be adopted. In the above-mentioned embodiment, the aperture stop 24 may be adjusted by the control unit 50, for example, so that bright field light from the illumination member 3 does not enter the imaging lens 23. In this case, for example, when imaging the optical lens 1, the aperture stop 24 is adjusted under the control of the control unit 50 so that a contrast appropriate for image processing is obtained. In addition, for example, the distance between the optical lens 1 and the imaging unit 2 and the distance between the optical lens 1 and the illumination member 3 may also be adjusted under the control of the control unit 50. In the above-mentioned embodiment, for example, a position adjustment mechanism for the optical lens 1, a position adjustment mechanism for the imaging unit 2, or a position adjustment mechanism for the illumination member 3 is provided, and the above-mentioned distances are adjusted by these position adjustment mechanisms (none of which are shown).

[0095] In the first embodiment described above, the second rotating unit 42 is configured, for example, by a goniostage, but is not limited to this as long as it is configured to rotate the illumination member 3 and the first rotating unit 41 approximately around the axis O2.

[0096] In the first embodiment described above, the determination as to whether rotation of the first rotating unit 41 is necessary (step S9) may be performed before processing (step S5) of the image captured by the imaging unit 2. That is, after acquiring a plurality of images captured by arranging the optical lens 1 and the illumination member 3 in a plurality of different positional relationships, the plurality of images may be processed collectively.

[0097] A configuration is adopted in which the moving member 242b of the planar moving unit 242 constituting the optical lens inspection device 200 in the above-mentioned second embodiment is connected to the illumination member 3 so as to change the irradiation angle of the light of the illumination member 3, for example, to obtain a modified example of the second embodiment. FIG. 24 is a side view showing the illumination member 3 and the moving mechanism 240 in the modified example of the second embodiment. The optical lens inspection device 200 in this modified example further includes an irradiation angle changing unit 233 that changes the irradiation direction 3D of the light of the illumination member 3. The irradiation angle changing unit 233 connects the illumination member 3 to the planar moving unit 242. The irradiation angle changing unit 233 is configured to be rotatable about the X-axis direction as a central axis. Therefore, with the rotation of the irradiation angle changing unit 233, the illumination member 3 rotates around an axis along the X-axis. The X-axis direction is a direction perpendicular to the moving direction of the moving member 242b. By rotating in a direction perpendicular to the moving direction of the moving member 242b in this way, the irradiation angle of the light from the illumination member 3 to the optical lens is changed. Therefore, light is irradiated onto the optical lens in accordance with the concave-convex shape of the optical lens. In other words, in the modified example shown in Fig. 24, the illumination member 3 can change the light irradiation angle without relying on the movement mechanism 240. According to the optical lens inspection device 200 in the second embodiment, the optical lens 1 is irradiated from a plurality of angles (a plurality of positions) by the illumination member 3.

[0098] In the above-described embodiment, the optical lens inspection device 100, 200 includes the second rotating unit 42, but may not include the second rotating unit 42. In this case, the intensity of the light irradiated by the illumination member 3 is increased, so that the dark field region 31, which is the boundary region between the bright and dark regions, is expanded. In this way, the intensity of the light irradiated by the illumination member 3 can be increased to expand the dark field region 31. In addition, by expanding the dark field region 31 in this way, the number of images required to capture the entire optical lens 1 is reduced. In this respect, it is preferable that the intensity of the light irradiated by the illumination member 3 is increased to an extent that the dark field region 31 can be expanded. If the dark field region 31 is expanded, it is considered that the dark field image of substantially the entire region of the optical lens 1 can be captured by only rotating the first rotating unit 41.

[0099] The embodiments disclosed herein are merely examples and are not limited to the above-mentioned contents. The scope of the present invention is defined by the claims, and it is intended to include all modifications within the scope of the claims and their equivalent meanings. [Explanation of symbols]

[0100] 1 Optical Lenses 2. Imaging unit 3 Lighting materials 3D Light Direction 4,240 Moving mechanism 5. Computers 11. Defects 21 Optical system 22 Imaging Device 23 Imaging lens 24 Aperture Diaphragm 31 Darkfield region 32 Brightfield region 33 Light source 41 First Rotating Section 41R Rotation direction of the first rotating part 42 Second Rotating Section 42S Rotation direction of the second rotating part 42a,242a Guide rail 42b, 242b Moving parts 50 Control section 51 CPU 52 ROM 53 RAM 100 Optical lens inspection equipment 101 Inspection System 102 Storage unit 103 Good product storage section 104 Defective Goods Storage Department 105,106,107 Transfer mechanism 230R Rotation direction of lighting components 233 Irradiation angle change unit 242 Planar moving part 242S Moving direction O1 Optical axis of optical lens O2 Rotating shaft of the second rotating part P1 Principal plane of optical lens C Center

Claims

1. An apparatus for inspecting an optical lens, comprising: an imaging unit that images the optical lens; an illumination member having a linear or curved shape that is disposed opposite the imaging unit with the optical lens interposed therebetween and that irradiates the optical lens with light; a first rotating unit that rotates the illumination member relatively to the optical lens substantially around an optical axis of the optical lens; a moving mechanism that moves the illumination member relative to the optical lens between a position approaching the optical axis and a position away from the optical axis; Equipped with the moving mechanism includes a second rotating unit that rotates the illumination member relatively to the optical lens about an axis that is located on a principal plane of the optical lens and includes a center of the optical lens; Optical lens inspection equipment.

2. An apparatus for inspecting an optical lens, comprising: an imaging unit that images the optical lens; an illumination member having a linear or curved shape that is disposed opposite the imaging unit with the optical lens interposed therebetween and that irradiates the optical lens with light; a first rotating unit that rotates the illumination member relatively to the optical lens substantially around an optical axis of the optical lens; a moving mechanism that moves the illumination member relative to the optical lens between a position approaching the optical axis and a position away from the optical axis; an illumination angle changing unit for changing an illumination direction of the light from the illumination member; Equipped with Optical lens inspection equipment.

3. 3. The optical lens inspection apparatus according to claim 1, The illumination member moves within a range in which bright field light from the illumination member does not enter the imaging unit. Optical lens inspection equipment.

4. 4. The optical lens inspection apparatus according to claim 3, An optical lens inspection device in which the illumination member moves within a range where bright field light from the illumination member does not enter the imaging unit and where the illumination member is not imaged by the imaging unit when a sample optical lens having the same shape as the optical lens is imaged in advance.

5. 5. The optical lens inspection apparatus according to claim 1, The illumination members are arranged in a straight line, An optical lens inspection device, wherein a linear width along which the illumination members are arranged is approximately the same as or larger than a diameter of the optical lens.

6. 6. The optical lens inspection apparatus according to claim 1, The optical lens inspection device further includes a control unit that determines whether the optical lens is good or bad based on the image captured by the imaging unit.

7. 1. A method for inspecting an optical lens, comprising: a first imaging step of irradiating the optical lens with light from an illumination member having a linear shape or a curved shape along a convex surface or a concave surface of the optical lens, and imaging the optical lens with an imaging unit disposed opposite the illumination member across the optical lens; a rotating step of rotating the illumination member relative to the optical lens substantially around an optical axis of the optical lens to place the optical lens and the illumination member in a positional relationship different from that in the first imaging step; a second imaging step of imaging the optical lens by the imaging unit while irradiating the optical lens with light from the illumination member after the rotating step; Equipped with The illumination member may be rotated relatively to the optical lens about an axis that is located on a principal plane of the optical lens and includes a center of the optical lens. Optical lens inspection method.

8. A method for inspecting an optical lens, comprising the steps of: a first imaging step of irradiating the optical lens with light from an illumination member having a linear shape or a curved shape along a convex surface or a concave surface of the optical lens, and imaging the optical lens with an imaging unit disposed opposite the illumination member across the optical lens; a rotating step of rotating the illumination member relative to the optical lens substantially around an optical axis of the optical lens to place the optical lens and the illumination member in a positional relationship different from that in the first imaging step; a second imaging step of imaging the optical lens by the imaging unit while irradiating the optical lens with light from the illumination member after the rotating step; Equipped with The optical lens inspection method further includes a step of changing a light irradiation direction of the illumination member.

9. 9. The optical lens inspection method according to claim 8, a sample imaging step of imaging a sample optical lens having the same shape as the optical lens by the imaging unit while illuminating the sample optical lens with the illumination member in a plurality of positional relationships in which the relative positions of the sample optical lens and the illumination member are different; an optical lens inspection method in which the relative positional relationship of the illumination member to the sample optical lens and the imaging unit when an image in which no bright field light from the illumination member enters is captured in the sample imaging process is adopted as the relative positional relationship of the illumination member to the optical lens and the imaging unit in the first imaging process and the second imaging process.

Images