JPWO2021059439A1 - Lens mount and lens checker - Google Patents

Abstract

An object of the present invention is to provide a lens mounting table for a test lens, which can reduce the size of a lens checker for observing a hidden mark engraved on the peripheral edge of the lens to be tested.
The test lens mounting table for the lens checker of the present invention includes a hollow cylindrical body (3b), a transparent member (3a) for mounting the test lens, and a condenser lens (4a, 4b, 4c). The transparent member (3a) for mounting the test lens is arranged on the top of the hollow cylindrical body (3b), and the diameter of the condenser lens (4a, 4b, 4c) is smaller than the inner diameter of the hollow cylindrical body (3b). The condenser lens (4a, 4b, 4c) is arranged so as to be movable in the horizontal direction inside the hollow cylindrical body (3b), and the horizontal movement of the condenser lens (4a, 4b, 4c) with respect to the lens under test. The irradiation position of the transmitted light can be moved to the peripheral edge of the lens to be inspected.

Description

The present invention relates to a lens mounting table to be inspected and a lens checker.

A hidden mark (also referred to as an "alignment mark") indicating the manufacturer of the lens, the type of lens, etc. is engraved on the surface of an optical lens such as a spectacle lens or a contact lens. Patent Document 1 proposes a lens checker including a hidden mark observation system for observing the hidden mark.

Japanese Unexamined Patent Publication No. 10-132707

The hidden mark is generally engraved near the peripheral edge of the lens. Therefore, the lens checker provided with the above-mentioned hidden mark observation system is a large one that requires a large-diameter optical system capable of covering the entire test lens.

In addition, even when a hidden mark is made visible and visualized by using a diaphragm as a schlieren optical system on the light source side, a relatively large-diameter optical system must be adopted for the condenser lens, the light receiving side lens, and the like. It was inevitable that the lens checker would become larger.

Therefore, an object of the present invention is to provide a lens checker for observing a hidden mark engraved on the peripheral edge of a lens to be inspected, which can be miniaturized, and a lens checker using the mount.

In order to achieve the above object, the lens mount for the lens checker of the present invention is
Includes a hollow cylinder, a transparent member for mounting the test lens, and a condenser lens.
The transparent member for mounting the lens to be inspected is arranged on the top of the hollow cylinder.
The diameter of the condenser lens is smaller than the inner diameter of the hollow cylinder.
The condenser lens is arranged inside the hollow cylinder so as to be movable in the horizontal direction and to be rotatable right or left.
By the horizontal movement of the condenser lens, the irradiation position of the transmitted light to the test lens can be moved to the peripheral edge portion of the test lens.

Further, the lens checker of the present invention is
Includes a light source, a base, a lens mounting base, a support, and a light receiving side optical system.
The base includes a pinhole type diaphragm means coaxially arranged with the light source.
The lens mounting table to be inspected is arranged in the center of the upper surface of the base so as to be movable in the vertical direction.
The support column rises from one end side on the base.
The light receiving side optical system is arranged at the upper end of the support column, and includes an objective lens, an imaging lens, and an imaging means in order from the test lens mounting base side.
The test lens mounting table is the test lens mounting table of the present invention.

According to the present invention, by configuring a test lens mounting table including a condensing lens arranged so as to be movable in the horizontal direction inside the hollow cylindrical body, the condensing lens is transmitted without increasing the diameter. The light irradiation range can be adjusted as appropriate, and the lens checker for observing the hidden mark engraved on the peripheral edge of the lens to be inspected can be miniaturized.

FIG. 1 is a perspective view showing an example of the configuration of the lens checker of the present invention. FIG. 2 is a cross-sectional view showing an example of the configuration of the lens checker of the present invention. FIG. 3 is a cross-sectional view of the lens checker shown in FIG. 1 as viewed from the AA direction. FIG. 4 is a schematic diagram illustrating the movement of light in the lens checker of the present invention. FIG. 5 is a diagram showing an example of a photograph taken by the lens checker of the present invention. FIG. 6 is a plan view showing an example of the configuration of the light-shielding switching means of the present invention. FIG. 7 is a schematic diagram illustrating parallax in a lens checker including the light-shielding switching means of the present invention. FIG. 8 is a diagram showing another example of a photograph taken by the lens checker of the present invention.

Next, the present invention will be described with an example. However, the present invention is not limited by the following description.

In the lens mounting table of the present invention, the condensing lens is a collimating lens unit including a plurality of condensing lenses, and the diameters of the plurality of condensing lenses are all smaller than the inner diameter of the hollow cylindrical body. The plurality of condenser lenses are arranged inside the hollow cylindrical body so as to be movable in the horizontal direction and can be rotated clockwise or counterclockwise. The irradiation position of the transmitted light may be movable to the peripheral edge of the lens to be inspected.

The lens checker of the present invention further includes a light-shielding switching means, and the light-shielding switching means can block the left half of the light-receiving range of the light-receiving optical system and the right half. The second knife edge is arranged side by side in the horizontal direction, and the light-shielding switching means is arranged so as to be movable in the optical path in the optical path of the imaging means, and the light-shielding switching means is horizontally moved. By locating the first knife edge and the second knife edge in the optical path of the imaging means, the imaging means may be able to capture a left-right differential image.

In the lens checker of the present invention, the light receiving side optical system may be rotatable clockwise or counterclockwise.

In the lens checker of the present invention, the rotation axis of the condenser lens and the rotation axis of the light receiving side optical system may be the same.

In the lens checker of the present invention, the rotation axis of the condenser lens and the rotation axis of the light receiving side optical system may be different.

Hereinafter, specific embodiments of the present invention will be described with reference to FIGS. 1 to 8. However, the following embodiments are examples, and the present invention is not limited thereto.

1 and 2 show an example of the configuration of the lens checker of the present invention. FIG. 1 is a perspective view, and FIG. 2 is a cross-sectional view. Further, FIG. 3 shows a cross-sectional view of the lens checker shown in FIG. 1 as viewed from the AA direction. As shown in the figure, this lens checker includes a light source 2, a base 1, a lens mounting base 3 to be inspected, a support column 5, and a light receiving side optical system described later. The lens mounting table 3 in the lens checker of FIGS. 1 to 3 is the lens mounting table of the present invention.

The base 1 includes a pinhole type diaphragm means 2a arranged coaxially with the light source 2. Examples of the diaphragm means 2a include a diaphragm plate in which a pinhole 2b having a diameter of about 50 μm is perforated in the center with respect to the irradiation light from the light source 2. The base 1 may be further provided with an operation dial 1a for adjusting the amount of light of the light source 2.

The lens mounting table 3 to be inspected is arranged at the center of the upper surface of the base 1. The test lens mounting table 3 includes a hollow cylindrical body 3b, a transparent member 3a for mounting the test lens, and a collimating lens unit 4. Examples of the hollow cylindrical body 3b include a black cylindrical plastic cylinder and the like. The transparent member 3a for mounting the lens to be inspected is arranged on the top of the hollow cylindrical body 3b. Examples of the transparent member 3a for mounting the lens to be inspected include a circular transparent glass plate, a circular transparent resin plate, and the like.

The inner diameter of the hollow cylindrical body 3b may be set according to the inner diameter of the condenser lens constituting the collimating lens unit 4 described later and the horizontal movement and rotational movement distance thereof. The thickness of the hollow cylinder 3b is, for example, 2 mm to 5 mm, and the height of the hollow cylinder 3b is, for example, 25 mm to 40 mm.

The transparent member 3a for mounting the lens to be inspected may be fitted in a recess provided at the top of the hollow cylindrical body 3b, for example, as shown in FIGS. 2 and 3. The diameter of the transparent member 3a for mounting the lens to be inspected may be appropriately adjusted so that it can be fitted into the top of the hollow cylindrical body 3b. The thickness of the transparent member 3a for mounting the lens to be inspected is, for example, 2 mm to 5 mm.

A support arm member 3c for cantilevering and supporting the lens mounting table 3 to be inspected is connected to the hollow cylindrical body 3b. The support arm member 3c may be integrally molded with the hollow cylindrical body 3b, or may be a member separate from the hollow cylindrical body 3b and connected to the hollow cylindrical body 3b at the time of use. good. The lens mounting table 3 to be inspected is arranged so as to be movable in the vertical direction by, for example, manually screwing the adjustment knob 3d that moves the support arm member 3c up and down. As described above, since the lens mounting table 3 to be examined can be moved in the vertical direction, the focusing position of the imaging means 9, which will be described later, can be appropriately changed and adjusted.

The collimating lens unit 4 includes three condenser lenses 4a, 4b, and 4c. The diameters of the three condenser lenses 4a, 4b, and 4c are all smaller than the inner diameter of the hollow cylinder 3b. The collimating lens unit 4 is supported in the air inside the hollow cylinder 3 in a cantilevered state by a slide-type guide member 4d horizontally provided on the base 1. Further, the collimating lens unit 4 is arranged so as to be movable in the horizontal direction by, for example, manually screwing the adjusting knob 4e attached to the sliding guide member 4d.

The horizontal movable distance of the condenser lenses 4a, 4b, and 4c can be adjusted according to, for example, the diameter of the condenser lenses 4a, 4b, and 4c. For example, if the diameters of the condenser lenses 4a, 4b, and 4c are 40 mm (φ40), the horizontally movable distance is, for example, −10 mm to 10 mm. Further, for example, if the condenser lenses 4a, 4b, and 4c exceed φ40 (for example, φ80 to φ100), the horizontally movable distance is, for example, −15 mm to 15 mm. The condenser lenses 4a, 4b, and 4c may all have the same diameter, or may have different diameters as long as the diameter is smaller than the inner diameter of the hollow cylindrical body 3b.

According to the present invention, by horizontally moving the condenser lenses 4a, 4b, and 4c, the irradiation position of the transmitted light on the test lens Le can be moved to the peripheral edge of the test lens Le. The movement of light in the lens checker of the present invention will be described with reference to the schematic diagram of FIG. The irradiation light from the light source 2 is refracted by the pinhole effect of the pinhole type aperture means 2a, and then is condensed by the collimating lens unit 4 including the condenser lenses 4a, 4b, and 4c and transmitted through the test lens Le. do. In FIG. 4, when the collimating lens unit 4 is in the position indicated by the solid line, as shown by the solid arrow, the light passes through the peripheral edge of the lens Le to be examined, but is to the left of the imaging lens unit 6 described later. And cannot be observed by the imaging means 9. On the other hand, when the collimating lens unit 4 is horizontally moved to the right to the position indicated by the alternate long and short dash line, the light passes through the peripheral edge of the lens Le to be examined and then the imaging lens as shown by the arrow of the alternate long and short dash line. It proceeds to the unit 6 and can be observed by the imaging means 9.

As shown in FIG. 4, the collimating lens unit 4 is arranged inside the hollow cylindrical body 3b so as to be rotatable right or left in addition to being movable in the horizontal direction. As the rotation mechanism of the collimating lens unit 4, a conventionally known one may be used. The rotationally movable distance of the condenser lenses 4a, 4b, and 4c can be adjusted according to, for example, the diameter of the condenser lenses 4a, 4b, and 4c. Since the collimating lens unit 4 can rotate clockwise or counterclockwise, the scattered light from the lens Le to be inspected can be more widely taken into the light receiving side optical system described later, and as a result, the inspection range is expanded and the reading performance is expanded. Can be improved. According to the present invention, it is also possible to provide a test lens mounting table 3 in which the collimating lens unit 4 does not rotate and moves only in the horizontal direction.

2 and 3 show an example in which the collimating lens unit 4 includes three condensing lenses 4a, 4b, and 4c, but the collimating lens unit 4 includes two condensing lenses. It may be four or more. Further, instead of the collimating lens unit 4, one condensing lens may be arranged inside the hollow cylindrical body 3b so as to be horizontally movable and rotatable.

The support column 5 rises from one end side on the base 1. The light receiving side optical system is arranged at the upper end of the support column 5, and includes an objective lens 6a, an imaging lens unit 6, and an imaging means 9 in this order from the test lens mounting table 3 side. FIG. 2 shows an example in which the imaging lens unit 6 includes three imaging lenses 6b, 6c, and 6d, but the imaging lens unit 6 may include two imaging lenses. However, it may be four or more. Further, one imaging lens may be used instead of the imaging lens unit 6. Examples of the imaging means 9 include CMOS and the like. The image data obtained by the imaging means 9 may be enlarged and displayed on a display screen of, for example, a personal computer (PC) or a tablet terminal connected by a cable so that a person can observe the image data. As shown in FIG. 1, the lens checker of the present invention may further have an operation knob 9a for finely adjusting the focus of the imaging means 9. The configuration of the lens checker of the present invention other than the lens mounting table 3 to be inspected may be the same as that of a conventionally known lens checker.

As shown in FIGS. 1 and 2, the lens checker of the present invention may further include a light-shielding switching means 8. The plan view of FIG. 6 shows an example of the configuration of the shading switching means 8. As shown in the figure, the light-shielding switching means 8 includes a first knife edge 8b capable of light-shielding the left half of the light-receiving range of the light-receiving optical system and a second knife edge 8a capable of light-shielding the right half. They are arranged side by side in the horizontal direction. Further, the light-shielding switching means 8 includes a first knife edge 8b and a second knife edge 8b and a second variable diaphragm means 7 capable of continuously changing and adjusting the optical path area by operating the diaphragm knob 7a or a dial (not shown). It may be arranged horizontally side by side with the knife edge 8a. FIG. 6 shows an example in which the first knife edge 8b and the second knife edge 8a and the variable drawing means 7 are integrally configured, but the first knife edge 8b and the second knife edge are shown. The 8a and the variable aperture means 7 may be configured to be operated individually. As shown in FIGS. 1 and 2, the light-shielding switching means 8 is arranged so as to be movable in the horizontal direction in the optical path of the imaging means 9. By horizontally moving the shading switching means 8, the first knife edge 8b and the second knife edge 8a are positioned in the optical path of the imaging means 9, so that the imaging means 9 can capture a left-right parallax image. Is. At this time, the light flux transmitted through the lens Le by the first knife edge 8b and the second knife edge 8a is diffracted by the knife edge effect to form an image, while the light flux of the blocked semicircular portion is formed. Since the image is surely cut, the image captured by the imaging means 9 can be obtained as a clear image without interfering with the light flux of the remaining semicircular portion. Further, by horizontally moving the shading switching means 8, the variable aperture means 7 is positioned in the optical path of the image pickup means 9, and the operation knob 7a or the dial is operated (whether manual or automatic), whereby the image pickup means 9 is used. The brightness and sharpness of the image obtained with can be adjusted.

According to the present invention, it is also possible to provide a shading switching device for a lens checker including a first knife edge capable of shading the left half of the light receiving range and a second knife edge capable of shading the right half of the light receiving range. Is. Further, according to the present invention, in the lens checkers shown in FIGS. 1 and 2, it is possible to provide a lens checker including the light-shielding switching means 8 and not including the lens mounting table 3 to be inspected.

As shown in FIG. 4, in the lens checker of the present invention, the light receiving side optical system may be rotatable clockwise or counterclockwise. As the rotation mechanism of the light receiving side optical system, a conventionally known one may be used. The rotationally movable distance of the light receiving side optical system is not particularly limited, and may be appropriately adjusted within a range in which the scattered light by the test lens Le can be received. Since the light receiving side optical system can be rotated clockwise or counterclockwise, the scattered light from the lens Le to be inspected can be taken in more widely, and as a result, the inspection range can be expanded and the reading performance can be improved. .. According to the present invention, it is possible to provide a lens checker in which the collimating lens unit 4 does not rotate and only the light receiving side optical system can rotate and move, and only the collimating lens unit 4 can rotate and move. It is also possible to provide a lens checker in which the light receiving side optical system does not rotate and move. When both the collimating lens unit 4 and the light receiving side optical system are rotatable, their rotation axes may be the same or different. FIG. 4 shows an example in which the collimating lens unit 4 and the light receiving side optical system have the same rotation axis.

Next, the operating procedure and observation procedure of the lens checker of the present invention will be described. In the lens checker of the present invention, the test lens Le (whether it is a round lens or a lens with a spectacle frame) is placed on the transparent member 3a for mounting the test lens on the test lens mounting base 3. The image of the transmitted light from the test lens Le is captured by the imaging means 9 while adjusting the amount of light of the light source 2 with the operation dial 1a. This imaging data is transmitted to a PC or the like and displayed on a display screen, and a person observes a hidden mark on the surface of the lens Le to be inspected. The focusing operation and the like at that time are the same as those in the conventionally known lens checker. Further, when observing the hidden mark, the shading switching means 8 may be used to obtain a clear image. Further, a holding mechanism for fixing the spectacles and the lens may be appropriately added to the lens mounting table 3 to be inspected.

According to the present invention, as described above with reference to FIG. 4, even if the irradiation light from the light source 2 is refracted by the pinhole effect of the pinhole type diaphragm means 2a, the peripheral portion of the lens Le to be inspected is formed. It is possible to irradiate the light from the collimating lens unit 4 without deviating from it. At this time, due to the horizontal movement of the condenser lenses 4a, 4b, and 4c included in the collimating lens unit 4, the condenser lenses 4a, 4b, and 4c used are not the conventional large-diameter lenses but small-diameter lenses. However, since the light can be moved to the peripheral portion of the lens Le to be inspected, the lens checker can be miniaturized. Further, in the lens checker of the present invention, the light receiving side optical systems such as the objective lens 6a and the imaging lenses 6b, 6c, 6d included in the imaging lens unit also have a small diameter instead of the conventional large diameter. Therefore, the lens checker can be miniaturized from this point as well. As a result, according to the present invention, it is possible to reliably observe the hidden mark engraved on the peripheral edge of the lens to be inspected Le without using a large-diameter optical system.

As an example, the procedure for observing the hidden mark of the spectacle lens framed in the spectacle frame will be described. First, the spectacle lens is placed on the transparent member 3a for mounting the test lens on the test lens mounting table 3, and a hidden mark engraved on the peripheral portion of the lens is found. At this time, even if the irradiation light from the light source 2 is emitted outside the spectacle frame, as described above, the adjustment knob 4e is manually rotated to collect the collection included in the collimating lens unit 4. By horizontally moving the optical lenses 4a, 4b, and 4c to the right or left and adjusting them so as to pass through the spectacle lens, the hidden mark can be confirmed as illustrated in FIG.

After confirming the hidden mark, the optical center position of the spectacle lens can be obtained, for example, as follows. That is, since two hidden marks are engraved at a position 17 mm to the left and a position 17 mm to the right from the optical center of the spectacle lens, the position moved toward the center of the lens by 17 mm, which corresponds to half of the distance of 34 mm between them. May be marked as the optical center of the spectacle lens to be inspected. If necessary, this marking may be used to evaluate the compatibility of the lens with the frame and the like.

Further, when the lens checker of the present invention includes the light-shielding switching means 8, it is possible to inexpensively and easily discriminate between scratches and foreign substances having a similar shape, such as dirt. In Japanese Patent Application Laid-Open No. 9-269276, a lighting unit integrated with a diffuser plate for observing a test lens is provided on a CCD camera or the like arranged to face each other so that the common axis can be adjusted to transmit the test lens. An example is described in which the brightness distribution related to the light intensity of transmitted light is measured from the obtained image data, and the brightness and the like are quantified and comparatively calculated to mechanically determine scratches and foreign matter. On the other hand, according to the present invention, it is inexpensive and easy only by adding a light-shielding switching mechanism without requiring an expensive luminance sensor or arithmetic processing means for digitizing image data required for mechanical determination in the same publication. In addition, it is possible to distinguish between scratches and foreign substances such as dirt.

In distinguishing between scratches and foreign matter such as dirt, the height of the lens mounting table 3 to be examined is first adjusted to a predetermined position, and then a plate called a target is placed on the lens mounting table 3 to be imaged. A predetermined MTF (spatial frequency) is secured by fine-tuning the focusing of 9 with the operation knob 9 and reading the index on the target.

Then, by horizontally moving the shading switching means 8, the first knife edge 8b and the second knife edge 8a are alternately positioned in the optical path of the imaging means 9, so that the left half and right half images can be obtained. Operate as. The above-mentioned focusing operation by the operation knob 9a and the horizontal movement operation of the shading switching means 8 are not limited to manual operations, and may be configured to be automatically performed in sequence.

Using the left and right parallax images obtained by the light-shielding switching means 8, the procedure for determining whether the surface of the lens Le to be inspected is a scratch or a foreign substance such as dust or dirt is described with reference to FIGS. 7 and 8. explain. Since the image pickup means 9 is focused on the surface of the lens Le to be examined by the above-mentioned initial setting, when the scratch 10a is present on the lens Le to be examined, it is indicated by reference numeral (A) in FIG. As described above, the image pickup means 9 forms an image at one point, and as shown in the region surrounded by the reference numeral A in FIG. 8, it is captured as a scratch image at one point. On the other hand, when the foreign matter 10c such as dust or dust having a similar shape is present in the test lens Le, the reference numeral in FIG. 7 is the amount of the foreign matter 10c floating from the surface of the test lens Le. As shown as B), the distance between the optical axis foci fluctuates, and in combination with the left and right knife edge effects, the positions are doubly displaced as shown in the region surrounded by the symbol B in FIG. That is, it is imaged and displayed as an image with parallax. As described above, since the difference between the two images is clear, the latter image can be confirmed as an image of a foreign substance that is not a scratch. As described above, according to the present invention, it is possible to discriminate between scratches and foreign substances such as dust and dirt by human inspection with high accuracy, low cost and easy without using expensive mechanical arithmetic processing means. Can be done. The scratches 10b and the like on the back surface of the lens Le to be inspected can also be discriminated in the same manner as the case of the front surface of the lens Le to be inspected if the back surface of the lens Le to be inspected is focused.

As described above, according to the present invention, it is possible to reduce the size of the lens checker for observing the hidden mark engraved on the peripheral edge of the lens to be inspected.

1 Base 2 Light source 2a Pinhole type aperture means 3 Test lens mounting base 3a Transparent member for mounting the test lens 3b Hollow cylindrical body 3d, 4e Adjustable knob 4 Collimating lens unit 4a, 4b, 4c Condensing lens 4d Slide Formula Guide member 6a Objective lens 6 Imaging lens unit 6b, 6c, 6d Imaging lens 7 Variable aperture means 8a Second knife edge 8b First knife edge 9 Imaging means

Claims (7)

Includes a hollow cylinder, a transparent member for mounting the test lens, and a condenser lens.
The transparent member for mounting the lens to be inspected is arranged on the top of the hollow cylinder.
The diameter of the condenser lens is smaller than the inner diameter of the hollow cylinder.
The condenser lens is arranged inside the hollow cylinder so as to be movable in the horizontal direction and to be rotatable right or left.
By the horizontal movement of the condenser lens, the irradiation position of the transmitted light to the test lens can be moved to the peripheral portion of the test lens.
A lens mount for the lens checker. The condenser lens is a collimating lens unit including a plurality of condenser lenses.
The diameters of the plurality of condenser lenses are all smaller than the inner diameter of the hollow cylinder.
The plurality of condenser lenses are arranged inside the hollow cylinder so as to be movable in the horizontal direction and to be rotatable right or left.
By the horizontal movement of the plurality of condenser lenses, the irradiation position of the transmitted light to the test lens can be moved to the peripheral edge portion of the test lens.
The lens mounting table according to claim 1. Includes a light source, a base, a lens mounting base, a support, and a light receiving side optical system.
The base includes a pinhole type diaphragm means coaxially arranged with the light source.
The lens mounting table to be inspected is arranged in the center of the upper surface of the base so as to be movable in the vertical direction.
The support column rises from one end side on the base.
The light receiving side optical system is arranged at the upper end of the support column, and includes an objective lens, an imaging lens, and an imaging means in order from the test lens mounting base side.
The test lens mount is the test lens mount according to claim 1 or 2.
Lens checker. In addition, it includes a light-shielding switching means.
In the light-shielding switching means, a first knife edge capable of light-shielding the left half of the light-receiving range of the light-receiving optical system and a second knife edge capable of light-shielding the right half are arranged side by side in the horizontal direction. And
The shading switching means is arranged so as to be movable in the horizontal direction in the optical path of the imaging means.
By horizontally moving the shading switching means, the first knife edge and the second knife edge are positioned in the optical path of the imaging means, so that the imaging means can capture a left-right parallax image. Is,
The lens checker according to claim 3. The light receiving side optical system can rotate clockwise or counterclockwise.
The lens checker according to claim 3 or 4. The rotation axis of the condenser lens and the rotation axis of the light receiving side optical system are the same.
The lens checker according to claim 5. The rotation axis of the condenser lens and the rotation axis of the light receiving side optical system are different.
The lens checker according to claim 5.

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