Observation device for surface profile of micro spherical lens

Abstract

The utility model discloses a device for observing the surface profile of a micro spherical lens, which is suitable for timely observing and monitoring the surface shape (profile) of a rough grinding surface on a production line. The magnified'light leakage seam 'image of the rough grinding surface profile and the knife edge profile is displayed on the screen, so that the condition of the rough grinding surface shape of the spherical surface can be quickly judged, the subsequent accurate grinding and polishing processing and the stability of the overall work efficiency and quality of a production line are facilitated, and the device can be used for observing the rough grinding plane, spherical surface or aspheric surface profile of the lens. The method is suitable for magnification observation of production processes of various surface profiles such as planes or curved surfaces, and is wide in application range.

Description

Technical Field

[0001] The invention relates to a technology for detecting the surface profile of an optical lens, and in particular to detecting the profile of a spherical surface of a micro lens. Background Art

[0002] In the field of precision optical technology, a large number of small-sized optical lenses are used, such as cylindrical lenses CLENS used in optical communication devices. The typical size is an axially transparent plano-convex lens with a cylindrical diameter of 1.0 mm and a curvature radius of 1.2 mm on its convex spherical surface. Spherical surface processing is performed on a 20-axis machine, such as Figure 1 As shown, a concave grinding surface with a suitable curvature radius is provided on a fixed abrasive (commonly known as a pill) 1, and a lens 2 to be processed is clamped by a fixture, and its processed surface is placed in the concave grinding surface of the pill 1. The lens 2 and the pill 1 rotate and swing relative to each other to achieve grinding.

[0003] The spherical surface processing process is divided into three sub-processes: rough grinding (commonly known as opening the radius), fine grinding and polishing. Each process takes a few minutes. The polished spherical surface can be checked by using the interference template to see the aperture (Newton ring) to detect whether its surface shape is qualified. The spherical surface after fine grinding is already bright, so the interference template can also be used to judge whether its surface shape (contour) meets the process requirements. Only the lens spherical surface after rough grinding is frosted, and the interference aperture cannot be seen. In addition, due to the small diameter of lens 2, the concave surface shape of pill 1 will change after a period of processing, which also leads to the unstable surface shape of lens 2 after rough grinding, affecting the subsequent fine grinding and polishing. Therefore, it is hoped that the spherical surface contour of the lens after rough grinding can be observed on the production line to ensure the efficiency and quality of subsequent processing and to ensure the stability of the overall production rhythm and quality. Summary of the invention

[0004] The technical problem that this application needs to solve is to design a device that can observe the surface profile of tiny lenses after rough grinding, so that "qualified" rough-ground parts can flow to subsequent fine grinding and polishing processes, rather than estimating the quality of rough grinding based solely on workers' experience, to ensure the overall work efficiency and quality stability of production.

[0005] The specific contents are as follows:

[0006] The present application discloses an observation device for the surface profile of a micro spherical lens, wherein the observed lens 2 and the blade plate 4 are fixed by fixing devices respectively, the coarse-ground surface of the observed lens 2 is in contact with the blade 41 of the blade plate 4, a floodlight 5 and an industrial camera system 6 are arranged opposite to each other on both sides of the contact point, the floodlight 5 illuminates the contact point, and the industrial camera system 6 displays the image of the light leakage bright gap between the coarse-ground surface profile of the observed lens 2 and the profile of the blade 41 at the contact point on a screen.

[0007] Furthermore, the width of the rough-ground surface of the lens 2 does not exceed 3 mm, and the width of the blade 41 of the blade plate 4 does not exceed 3 mm.

[0008] Preferably, the fixing device of the observed lens 2 is a lens positioning ring 3, or a V-groove plus an elastic pressure plate mechanism.

[0009] Preferably, the industrial camera system 6 is a monocular zoom lens plus a digital camera and a display screen, and the comprehensive magnification of the industrial camera system 6 is not less than 50 times.

[0010] Preferably, the blade piece 4 is made of metal or ceramic, and the thickness of the blade piece 4 is not less than 0.1 mm and not more than 0.2 mm.

[0011] Preferably, the cutting edge piece 4 is a multi-cutting edge piece with two or more cutting edges 41 .

[0012] The present application discloses a micro spherical lens surface profile observation device, which is an electronic magnification observation device for the rough grinding surface profile, and is an observation device with an accuracy between that of a profiler interferometer and that of a rough human eye directly observing a knife edge.

[0013] Compared with the prior art, this device can achieve the following beneficial effects:

[0014] This device brings the inspected surface of the lens into contact with a standard knife edge, and uses a digital camera system to display the magnified "light leakage gap" image between the lens surface contour and the standard knife edge contour on the screen. It is used to quickly and quantitatively judge the quality of the rough-ground surface contour, rather than estimating the quality of the rough-ground surface based solely on the workers' experience. This helps with subsequent fine grinding and polishing processing, and helps stabilize the work efficiency and quality of the production line.

[0015] This device is designed for observing the surface profile of tiny lenses with a diameter not exceeding 3mm, but is also suitable for observing the surface profile of "not too small" lenses with a diameter greater than 3mm; this device is designed for observing the spherical profile of lenses, but is also suitable for observing the plane profile or aspherical profile of lenses, that is, it is suitable for magnified observation of production processes of various surfaces such as planes or curved surfaces, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of using pills to process the spherical surface of a lens;

[0017] Figure 2 A schematic diagram of a device for observing the surface profile of a lens;

[0018] Figure 3 It is a schematic diagram comparing the surface profile of the lens with the standard knife edge profile;

[0019] Figure 4It is a schematic diagram comparing the surface profile of the lens with the standard knife edge profile;

[0020] Figure 5 Schematic diagram of a knife-edge sheet with multiple knife edges. DETAILED DESCRIPTION

[0021] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application.

[0022] like Figure 1 As shown, the surface shape of the existing micro-lens spherical surface after rough grinding cannot be observed, and the quality of rough grinding is controlled only by the workers' experience. Then, the quality of rough grinding is reversely verified by observing the interference aperture after fine grinding, and then the rough grinding parameters are adjusted. This will affect the overall production rhythm and quality stability, especially when changing varieties and specifications (processing lenses with different diameters and spherical curvature radii), which has a great impact on production.

[0023] The present application discloses a device for observing the surface profile of a micro lens, such as Figure 2 As shown, the basic principle of the device is to use a knife edge ruler to observe the contour, but instead of using the human eye to directly observe the light leakage from the knife edge, the electronic image of the light leakage is observed through an amplification system, so as to quantitatively judge the quality of the rough-ground surface contour. In this embodiment, taking the observation of the convex spherical surface of a tiny lens as an example, the standard knife edge used is a concave arc shape.

[0024] Figure 2 In the embodiment, the lens 2 held by the fixture is inserted downward into the through hole of the lens positioning ring 3. The lens positioning ring 3 is fixed by a bracket (not shown in the figure), and the blade piece 4 is fixed on the bracket 7. The bracket 7 can be accurately translated so that its concave arc blade 41 faces upward and aligns with the vertical axis of the lens positioning ring 3. Relying on its own gravity, the measured spherical surface of the lens 2 falls on the concave arc blade 41 of the blade piece 4 and contacts. A floodlight 5 is set on the right side of the blade piece 4, and a monocular zoom lens industrial camera 6 is set on the left side of the blade piece 4. The digital video signal of the industrial camera 6 is output to the display screen (not shown in the figure). The combined magnification of the monocular zoom lens industrial camera 6 and the display screen is more than 50 times. Figure 3 and Figure 4 It is the magnified spherical contour and blade contour of lens 2, or the “blade leak bright line” diagram displayed on the screen.

[0025] For the lens positioning ring 3, taking the R1.2 spherical surface of a plano-convex lens with a cylindrical diameter of 1.0 mm as an example, in order to facilitate the insertion and removal of the inspected lens and to ensure that the deflection angle relative to the vertical axis is not large, the inner aperture of the lens positioning ring 3 can be set to 1.03 mm and the cylindrical matching height to 2.0 mm.

[0026] The floodlight 5 and the industrial camera 6 should be placed at opposite positions, that is, the industrial camera 6 needs to see the backlight. When observing the "blade leaking bright line", the surrounding environment usually needs to be a dark background, and the floodlight 5 emits uniform and soft light.

[0027] The concave arc blade 41 of the blade piece 4 is a finely ground arc cylinder with a standard contour and a curvature radius of 1.2 mm. In order to make the concave circular blade 41 wear-resistant and durable, the material of the blade piece 4 is preferably metal or ceramic, for example, the material is a mold steel sheet. The thickness of the blade piece 4 needs to be appropriate. If it is too thick, it is not conducive to observing the "leaking bright line". If it is too thin, on the one hand (due to the slight swing of the lens being inspected), the observed position may not be the axial section of the lens. On the other hand, the rigidity of the blade is insufficient. Therefore, the thickness of the blade piece 4 is preferably 0.1 mm to 0.2 mm.

[0028] like Figure 3 and Figure 4 When the combined magnification of the monocular zoom lens industrial camera 6 plus the display screen is 100 times, the lens 2 with a column diameter of 1.0 mm is 100 mm wide on the display screen, and when the width of the concave circular blade 41 is designed to be 1.5 mm, it is 150 mm wide on the display screen. Figure 3 The figure shows the case where the radius of curvature of the rough-ground surface is too large. The "bright line of gap" appears when the two sides are in contact but the center is gapped. This situation is commonly known as low aperture of the lens. Figure 4 The figure shows the case where the radius of curvature of the rough ground surface is too small. The "bright line of gap" is that the center is in contact but the gaps are on both sides. This situation is commonly known as the high aperture of the lens. The subsequent process hopes to obtain a good rough ground surface with a radius of about 10 circles lower ( Figure 3 The central seam width is about 3um). After the system is magnified 100 times, the central seam width on the screen is 0.3mm. The human eye observes the bright line of the seam width on the screen to quantitatively judge the quality of the rough-ground surface of the inspected part. That is, if the central seam width between the lens contour and the arc blade contour is within 0.3mm, it is good, otherwise it is bad.

[0029] use Figure 2 With the device shown, workers can quickly observe the contour of the rough-ground surface and know whether the rough-ground surface is good or bad, so as to timely trim the concave ground surface of the pill 1 and adjust other process parameters, so that the material supplied from the rough-ground process to the next process always has a stable and consistent initial surface shape, reducing the incoordination between processes.

[0030] It should be pointed out that: Figure 2The device shown is developed for observing the rough-ground profile of tiny lenses with a column diameter of less than 3 mm, so the width of the blade 41 does not exceed 3 mm, and the comprehensive magnification of the industrial camera system is not less than 50 times, but the device is also suitable for observing the rough-ground profile of "not too small" lenses with a diameter greater than 3 mm, just by adjusting the blade size and magnification accordingly. The industrial camera system can also have various forms, not limited to the combination of a monocular zoom lens industrial camera plus a screen;

[0031] Figure 2 The structure for fixing the lens 2 to be tested is not limited to the lens positioning ring 3, and can also be designed as a fixing structure of a V-shaped groove plus an elastic pressure plate. In this case, the lens does not fall on the knife edge 41 by its own gravity, but is manually placed so that the contours are in contact and then the lens is pressed to stabilize.

[0032] The blade piece 4 can be designed to have two or more blade edges 41, such as Figure 5 As shown, one blade 4 can be used for observing the profile of lenses of different specifications (lens diameter and spherical curvature radius). For example, three blade edges 41 with curvature radii of R1.2, R1.4 and R1.8 are arranged at intervals on one side of the blade. Figure 2 By translating the bracket 7 below the blade piece 4 perpendicularly to the paper surface, the device can be used to observe the rough ground spherical surfaces of three specifications: R1.2, R1.4 and R1.8.

[0033] It should be pointed out that this device is designed for observing the rough ground spherical surface profile of the lens, but it is also suitable for observing the plane profile and aspherical (such as parabolic) profile of the lens, and it only needs to adjust the profile shape of the blade accordingly.

[0034] The above are only the preferred embodiments and technical principles used in this application. For those skilled in the art, more other equivalent embodiments can be produced without departing from the concept of the present invention. The protection scope of the present invention is determined by the scope of the attached claims.

Claims

1. A device for observing the surface profile of a micro spherical lens, characterized in that: The observed lens (2) and the blade plate (4) are respectively fixed by fixing devices, the rough ground surface of the observed lens (2) contacts the blade edge (41) of the blade plate (4), the floodlight (5) and the industrial camera system (6) are arranged opposite to each other on both sides of the contact point, the floodlight (5) illuminates the contact point, and the industrial camera system (6) displays an image of a light leakage bright gap between the rough ground surface contour of the observed lens (2) and the blade edge (41) at the contact point on a screen.

2. A micro spherical lens surface profile observation device as claimed in claim 1, characterized in that: The width of the rough ground surface of the observed lens (2) does not exceed 3 mm, and the width of the blade (41) of the blade sheet (4) does not exceed 3 mm.

3. A micro spherical lens surface profile observation device as claimed in claim 1, characterized in that: The fixing device for the observed lens (2) is a lens positioning ring (3), or a V-shaped groove plus an elastic pressure plate mechanism.

4. A micro spherical lens surface profile observation device as claimed in claim 1, characterized in that: The industrial camera system (6) is a monocular zoom lens plus a digital camera and a display screen, and the comprehensive magnification of the industrial camera system (6) is not less than 50 times.

5. The micro spherical lens surface profile observation device according to claim 1, characterized in that: The material of the blade piece (4) is metal or ceramic.

6. A micro spherical lens surface profile observation device as claimed in claim 5, characterized in that: The thickness of the blade piece (4) is not less than 0.1 mm and not more than 0.2 mm.

7. A micro spherical lens surface profile observation device as claimed in claim 5, characterized in that: The blade piece (4) is a multi-blade piece type with two or more blade edges (41).

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