CN206593572U - A kind of instrument for accurately measuring optical mirror slip center thickness - Google Patents

Abstract

A tool for accurately measuring the center thickness of an optical lens, comprising a horizontal workbench, a vertical fixing frame, and a dial indicator, the vertical fixing frame is vertically connected with the horizontal workbench through threads, and the dial gauge is fixed on the vertical fixing frame, and is characterized in that It also includes a correction connection seat, an optical glass measuring fixture, a center correction tool and a return part; the horizontal workbench is vertically connected to the correction connection seat through threads, the optical glass measuring fixture is vertically inserted into the groove of the correction connection seat, and the dial indicator The head is suspended directly above the optical glass measuring fixture, and the center of the dial gauge head and the center of the optical glass fixture are on the same axis; there is a fine-adjustable gap between the outer diameter of the lower end of the optical glass measuring fixture and the inner diameter of the groove of the calibration connection seat The outer side of the correction connection seat is provided with a number of fastening positioning screws; the accuracy rate of the utility model for measuring the center thickness of the optical lens reaches more than 90%, and the detection speed is fast and the efficiency is high.

Description

A Tool for Accurately Measuring the Center Thickness of Optical Lens

technical field

The utility model relates to the technical field of optical processing, directly affects the qualification rate in the optical processing process, and is a tool for measuring the center thickness of optical glass lenses.

Background technique

In the field of modern optical technology, the processing accuracy of optical lenses is getting higher and higher, especially for optical lenses used in optical imaging systems, the center thickness tolerance of the design requirements is plus or minus 0.01mm.

When the existing measurement tools detect the center thickness of the concave-convex optical lens, since the lens to be measured is placed on the horizontal workbench of the table base, the weight of the lens itself is stable, and then vertically measured with a dial indicator, in order to improve the accuracy, it is often necessary to Measure several points to find the closest size (refer to attached drawings 1 and 2). It can be seen from the figure that there is an angle θ ^· between the central optical axis of the lens and the absolute vertical line, and the measurement result is H ^· , but The real size H=H ^/ cosθ, so there is a measurement error, and the stability is also due to the degree of lens eccentricity, as well as the degree of cleanliness of the plane or lens surface, which leads to great randomness in the measurement results, which in turn affects the glass in the optical processing process. Pass rate, while multi-point measurement also wastes a lot of time, and the efficiency is not high.

Contents of the invention

The technical problem to be solved by the utility model is to provide a tool for accurately measuring the thickness of an optical lens, mainly a concave-convex lens, especially a lens center whose convex surface is close to a hemisphere, in order to reduce measurement errors and improve efficiency.

In order to achieve the above purpose, the technical solution adopted by the utility model is: a tool for accurately measuring the center thickness of the optical lens, including a horizontal workbench, a vertical fixing frame, and a dial gauge. The meter is fixed on the vertical fixing frame, which is characterized in that it also includes a calibration connection seat, an optical glass measurement fixture, a center correction tool and a return part; the horizontal workbench is vertically connected to the correction connection seat through threads, and the optical glass measurement fixture is inserted vertically In the groove of the correction connecting seat, the dial gauge head is suspended directly above the optical glass measuring fixture, and the center of the dial gauge head and the center of the optical glass fixture are on the same axis; the outer diameter of the lower end of the optical glass measuring fixture is aligned with the correction There is a fine-tunable gap between the inner diameters of the connecting seat grooves, and a number of fastening positioning screws are provided on the outside of the correcting connecting seat; the upper end of the optical glass measuring fixture is provided with a groove that can be vertically inserted into the center correction tool, and the center correction tool The outer wall of the insertion end is closely attached to the inner wall of the groove at the upper end of the optical glass measuring fixture; the upper end of the center correction tool is provided with a center hole that can be vertically inserted into the head of the dial gauge, and the depth of the center hole is greater than the length of the head of the dial gauge.

Preferably, the normalized part adopts a lens whose center thickness has been accurately measured and has the same specifications as the lens to be tested.

The depth at which the dial indicator head is inserted into the center hole of the center correction tool is 1/4 to 2/3 of the depth of the center hole.

In the utility model, in order to measure lenses of various specifications, glass fixtures with various apertures can be made on a high-precision numerical control lathe, and corresponding fixtures can be selected for use during application.

The measuring tool of the utility model has no error in theory, but it is related to the processing accuracy of the fixture and the spherical radius of the lens in actual operation. Generally, for a fixture with a processing accuracy of 0.02mm and a lens with a spherical error of 0.5%, the thickness error of the measurement center is 0.005mm Within , fully meet the measurement accuracy requirements, and the use of higher precision fixtures can reduce measurement errors. With rotational self-centering, the consistency of the measurement is also unstable.

Beneficial effects: the accuracy rate of the utility model for measuring the center thickness of the optical lens reaches more than 90%, and the detection speed is fast and the efficiency is high.

Description of drawings

Fig. 1 is a schematic diagram of an existing measurement tool.

Fig. 2 is a schematic diagram of the measurement state of the existing measurement work.

Fig. 3 is a schematic diagram of the measurement tool of the embodiment.

Fig. 4 is a partial schematic diagram of the center correction during the measurement of the embodiment.

Fig. 5 is a partial schematic diagram of the zeroing of the dial indicator during measurement in the embodiment.

Fig. 6 is a partial schematic diagram of the measurement lens of the embodiment.

In the figure, 1-working table, 2-vertical fixing frame, 3-dial indicator, 4-returning parts, 5-lens to be tested, 6-meter head, 7-fixture, 8-fastening positioning screw, 9-correction Connection base, 10-center correction tool.

detailed description

Below in conjunction with embodiment and accompanying drawing, the utility model is described in detail.

Embodiment: The tool for accurately measuring the center thickness of an optical lens refers to accompanying drawing 3, and mainly includes a horizontal worktable 1, a vertical fixing frame 2, and a dial indicator 3. The vertical fixing frame 2 is vertically connected with the horizontal working table 1 through threads, and the dial indicator 3 is fixed on the vertical fixing frame 2, and its main feature is that it also includes a correction connection seat 9, an optical glass measuring fixture 7, a center correction tool 10 and a return part 4; the horizontal workbench 1 is vertically connected with the correction connection seat 9 through threads, The optical glass measuring jig 7 is vertically inserted into the groove of the calibration connection seat 9, the dial gauge head 6 is suspended directly above the optical glass measuring jig 7, and the center of the dial gauge head 6 and the center of the optical glass jig 7 are on the same axis There is a gap that can be fine-tuned between the outer diameter of the lower end of the optical glass measuring fixture 7 and the inner diameter of the groove of the correction connecting seat 9, and some fastening set screws 8 are provided on the outside of the correcting connecting seat 9; the upper end of the optical glass measuring fixture 7 is provided with adjustable Insert vertically into the groove of the center correction tool 10, and the outer wall of the insertion end of the center correction tool 10 is closely attached to the inner wall of the groove at the upper end of the optical glass measuring fixture 7; Hole, the depth of the central hole is greater than the length of the dial indicator head 6.

When measuring in the embodiment, first insert the optical glass measurement jig 7 vertically into the groove of the calibration connection seat 9, and insert the center calibration tool 10 vertically into the upper groove of the optical glass measurement jig 7 (refer to Figure 4). Since the inner wall of the groove at the upper end of the optical glass measuring fixture is closely matched with the outer diameter of the lower end of the centering correction tool with high precision, the coaxiality of the two can be guaranteed. When correcting the center, the dial indicator head 6 is inserted into about 1/4～2/3 of the center hole of the center correction tool 10 . Since there is a fine-adjustable gap between the outer diameter of the lower end of the optical glass measuring fixture 7 and the inner diameter of the groove of the correction connecting seat 9, the optical glass measuring fixture can be self-centered by rotating and translating the optical glass measuring fixture to ensure that the dial indicator head and the optical glass measuring fixture are at the same time. axis. After centering, evenly lock the plurality of fastening positioning screws 8 on the calibration connection base 9 to the optical glass measurement fixture (refer to Figure 3 ) to ensure that the axis will not deviate during the measurement.

Dial gauge zeroing: Place the high-precision zeroing part 4 of known size between the dial gauge head and the optical glass measuring fixture (refer to Figure 5), the dial gauge head is in contact with the zeroing part, and adjust the dial gauge Dial scale, so that the current reading of the dial indicator is equal to the height of the return part, remove the return part, and the zero scale of the dial indicator is the relative size of the upper end surface of the optical glass measuring fixture.

Measurement: Place the convex surface of the lens to be tested on the optical glass measuring fixture (refer to Figure 6), the dial gauge head contacts the concave surface of the lens to be tested, rotate the lens, and measure the internal diameter of the optical glass measuring fixture and the convex spherical surface of the lens, Under the combined action of the dial indicator head and the concave spherical surface of the lens, the optical axis of the lens to be tested is coaxial with the optical glass measuring fixture and the dial indicator head, and the central optical axis of the lens is coaxial with the optical glass measuring fixture and the dial gauge. There is no included angle between the coaxial lines of the meter head, and the included angle θ between the upper surface and the horizontal plane of the lens has nothing to do with the center thickness of the lens due to the centering of the lens. At this time, the measured lens size is h2. When the convex surface radius R of the lens and the inner diameter Φ of the optical glass measuring fixture are known, the size of h1 can be easily calculated, then the actual size of the lens is H=h1+h2.

In order to improve efficiency in mass production, you can use the same specification lens that has been accurately measured in the center thickness as a zeroing part, then you can directly measure the absolute value of the lens to be tested without calculation; or use the same specification that has accurately measured the center thickness If the standard lens is used as a reference, the relative value of the lens to be tested can be directly measured without calculation. Both of the above two methods can measure the center thickness conveniently, quickly and accurately, and greatly improve the efficiency.

In the embodiment, in order to measure lenses of various specifications, glass jigs with various apertures can be made on a high-precision CNC lathe. The general processing accuracy is 0.02 mm or higher, and the corresponding jigs are selected for use in applications.

The measurement application of the measuring tool in the utility model is carried out after the processing of the optical lens is completed. Generally, when the R value error of the optical lens is within 0.5%, the thickness error of the measurement center is within 0.005mm, which fully meets the measurement accuracy requirements, and the use of more High-precision fixtures can reduce measurement errors. Through the rotary self-centering, the consistency of the measurement is also unstable, the accuracy rate reaches more than 90%, and the detection speed is fast and the efficiency is high.

Claims (3)

1. A tool for accurately measuring the center thickness of an optical lens, including a horizontal workbench, a vertical fixing frame, and a dial indicator. The vertical fixing frame is vertically connected to the horizontal workbench through threads, and the dial gauge is fixed on the vertical fixing frame. Its features It also includes a correction connection seat, an optical glass measurement fixture, a center correction tool and a return part; the horizontal worktable is vertically connected to the correction connection seat through threads, and the optical glass measurement fixture is vertically inserted into the groove of the correction connection seat. The meter head hangs directly above the optical glass measuring fixture, and the center of the dial indicator head and the center of the optical glass fixture are on the same axis; the outer diameter of the lower end of the optical glass measuring fixture and the inner diameter of the groove of the calibration connection seat can be fine-tuned The outer side of the correction connection seat is provided with a number of fastening positioning screws; the upper end of the optical glass measurement fixture is provided with a groove that can be vertically inserted into the center correction tool, and the outer wall of the insertion end of the center correction tool is indented with the upper end of the optical glass measurement fixture. The inner wall of the groove is closely attached; the upper end of the center correction tool is provided with a center hole that can be vertically inserted into the head of the dial gauge, and the depth of the center hole is greater than the length of the head of the dial gauge. 2. The tool according to claim 1, characterized in that the normalized part adopts a lens whose center thickness has been precisely measured and has the same specifications as the lens to be tested. 3. The tool according to claim 1, characterized in that the depth at which the dial indicator head is inserted into the center hole of the center correction tool is 1/4 to 2/3 of the depth of the center hole.