TWI675225B - Micro distance les detection device - Google Patents

Abstract

The invention is a micro-distance lens detection device, which is suitable for micro-distance detection of a lens to be tested with a surface. The micro-distance lens detection device includes a light source module, a diffuser, and a pattern test arranged in sequence Card, a collimator unit, and an image acquisition module, wherein the lens to be tested is disposed between the pattern test card and the collimator unit, and the surface of the lens to be tested and the light output from the pattern test card The micro-distance between the faces is less than 25 mm; accordingly, the micro-distance between the lens to be tested and the pattern test card can be optically adjusted for the lens under test Detection of a transfer function (modulation transfer function, MTF). Therefore, the installation space required by the lens detection device is small.

Description

Micro-distance lens detection device

The present invention relates to a lens detection device, and more particularly to a micro-distance lens detection device.

Lenses have been widely used in portable mobile devices, such as smart phones and digital cameras. During the manufacturing process, the lens quality will be changed due to process differences. Therefore, the lens must be tested before it leaves the factory to ensure that the manufactured lens meets the original design specifications, such as the modulation transfer function (MTF). ) Has been a common indicator for evaluating the optical quality of a lens on the market today.

Referring to FIG. 1, a lens detection device generally used at present is mainly composed of a light source module 11, a pattern test card 12, and an image capturing module 13. The light emitted from the light source module 11 passes through the pattern test card 12 and is used to provide a test pattern required by the lens 14 to be tested. The lens 14 to be tested is placed at the test position, the image formed by the test pattern 14 through the lens 14 to be tested is acquired by the image capturing module 13 and transmitted to the host 15, and the captured image is analyzed by the host 15.

However, due to the conjugate relationship between the object distance and the image distance, the farther the object distance is, the closer the image distance is. On the contrary, the closer the object distance is, the further the image distance is. The distance between the surface of the lens 14 to be tested and the pattern test card 12) is detected between a specific range, about 320 mm to 500 mm. Once the distance between the lens 14 to be tested and the pattern test card 12 When it is smaller than the foregoing range, especially in a state where the distance is the object distance (that is, the distance between the surface of the lens 14 to be tested and the pattern test card 12 is less than 25 mm), the image capturing module 13 must be set to The measuring lens 13 is at an infinite distance, which causes a great demand for equipment space, which is disadvantageous to the setting of the detection device.

The object of the present invention is to provide a micro-distance lens detection device, which requires a small installation space to detect a lens to be measured in a micro-distance manner.

In order to achieve the foregoing object, the present invention is a micro-distance lens detection device, which is suitable for micro-distance detection of a lens to be measured with a surface. The micro-distance lens detection device includes a light source module and a diffuser which are sequentially arranged. Film, a pattern test card, a collimator unit, and an image acquisition module, of which:

The light source module provides a light; the diffusion sheet is provided on a path of the light to make the light passing therethrough more uniform; the pattern test card is provided on the path of the light after uniformity and has A light emitting surface generates a test pattern light type required by the lens under test by the light; the lens under test is disposed between the pattern test card and the collimator unit, and the surface of the lens under test and the The light emitting surface of the pattern test card is the micro distance, the micro distance is less than 25 mm; the collimator unit is used to receive the light pattern of the test pattern after passing the lens to be tested, and focus on the image capturing mode The image acquisition module is used to receive the light pattern of the test pattern focused by the collimator unit.

The effect of the present invention is that the sequential arrangement of the light source module, the diffusion sheet, the pattern test card, the collimator unit, and the image acquisition module allows the lens to be tested and the pattern test card to be at a small distance. Under the conditions, an optical resolution modulation transfer function (MTF) detection can be performed on the lens to be measured, and therefore, a small installation space requirement of the lens detection device is required. In addition, under the condition of the micro-distance between the lens to be tested and the pattern test card, the MTF can be accurately measured on and off the axis, and the lens to be tested does not matter whether its focus plane is on the lens MTF measurement can be performed inside or outside the lens mechanism.

Preferably, the lens to be tested has a lens barrel and a plurality of lens groups disposed in the lens barrel, and the lens group generates a focusing plane which is located inside the lens barrel or outside the lens barrel.

Preferably, the micro-distance is less than 10 mm.

Preferably, the test pattern of the pattern test card is a bar chart, an edge chart, or a slit chart.

Preferably, the collimator unit includes an imaging lens and a collimator, the imaging lens is used to receive the light pattern of the test pattern after passing through the lens to be tested, and the collimator is used to receive the light passing through the lens. The light pattern of the test pattern of the image capturing lens is focused on the image capturing module.

In addition, to achieve the foregoing object, the present invention is a micro-distance lens detection device, which is suitable for detecting a lens to be tested with a surface at a micro-distance. The micro-distance lens detection device includes a light source module sequentially arranged. , A filter, a pattern test card, a collimator unit, and an image capturing module, wherein: the light source module provides a light; the filter is arranged on the path of the light to filter Excluding light of a specific wavelength; the pattern test card is provided on the path of the filtered light and has a light emitting surface, and the light pattern of the test pattern required by the lens to be tested is generated by the light; The lens to be tested is set between the pattern test card and the collimator unit, and the micro distance between the surface of the lens to be tested and the light emitting surface of the pattern test card is less than 25 mm; the A collimator unit for receiving the light pattern of the test pattern after passing through the lens to be tested and focusing on the image capturing module; the image capturing module for receiving the test pattern focused by the collimator unit Light type.

The effect of the present invention is: by the sequential arrangement of the light source module, filter, pattern test card, collimator unit and image acquisition module, the micro-distance between the lens under test and the pattern test card Under the condition of the lens, an optical resolution modulation transfer function can be performed on the lens under test. function, MTF), so the installation space required by the lens detection device is small. In addition, under the condition of the micro-distance between the lens to be tested and the pattern test card, the MTF can be accurately measured on and off the axis, and the lens to be tested does not matter whether its focus plane is on the lens MTF measurement can be performed inside or outside the lens mechanism.

Preferably, the lens to be tested has a lens barrel and a plurality of lens groups disposed in the lens barrel, and the lens group generates a focusing plane which is located inside the lens barrel or outside the lens barrel.

Preferably, the micro-distance is less than 10 mm.

Preferably, the test pattern of the pattern test card is a bar chart, an edge chart, or a slit chart.

Preferably, the collimator unit includes an imaging lens and a collimator, and the imaging lens is used to receive the light pattern of the test pattern after passing through the lens to be tested, and the collimator is used to receive The test pattern of the imaging lens is light-focused and focused on the imaging module.

Please refer to FIG. 2. A micro-distance lens detection device according to a first embodiment of the present invention is suitable for detecting a lens 20 to be tested with a surface 21 at a micro-distance D. The micro-lens detection device includes A light source module 30, a diffusion sheet 40, a pattern test card 50, a collimator unit 60, and an image capturing module 70 are sequentially arranged, wherein the light source module 30 provides a light.

The diffusion sheet 40 is provided on the path of the light to make the light passing therethrough more uniform; accordingly, the light emitted by the light source module 30 is made more uniform after passing through the diffusion sheet 40, which improves the accuracy of the final measurement. .

The pattern test card 50 is provided on the path of the light after uniformity, and has a light emitting surface 51. The light pattern of the test pattern required for the lens 20 to be tested is generated by the light. In this embodiment, the pattern The light pattern of the test pattern of the test card 50 is a bar chart, but it is not limited thereto, and may also be an edge chart or a slit chart. It is worth noting that the light pattern of the test pattern of the pattern test card 50 will change with different optical characteristics of the lens 20 to be detected, and the pattern test card 50 can also be presented in a raster manner.

The lens to be tested 20 is disposed between the pattern test card 50 and the collimator unit 60, and the micro distance D is between the surface 21 of the lens to be tested 20 and the light emitting surface 51 of the pattern test card 50. The micro-distance D is 25 mm, but is not limited thereto. The micro-distance D may be within a range of less than 25 mm, for example, 5 mm, 6 mm, 7 mm, and 8 mm less than 10 mm. Centimeters, 9 millimeters, and so on. In this embodiment, the lens 20 to be tested has a lens barrel 22 and a plurality of lens groups 23 disposed in the lens barrel 22. The lens group 23 is composed of a plurality of lenses and generates a focusing plane 231. The plane 231 is located inside the lens barrel 22.

The collimator unit 60 is configured to receive the light pattern of the test pattern after passing through the lens 20 to be tested, and focus on the image capturing module 70. In this embodiment, the collimator unit 60 includes an image capturing lens 61 and a collimator 62, the taking lens 61 is used to receive the light pattern of the test pattern after passing through the lens 20 to be tested, and the collimator 62 is used to receive the light pattern of the test pattern passing through the image lens 61 Focusing on the image capturing module 70, the collimator 62 simulates an infinite distance between the lens 20 to be measured and the image capturing module 70.

The image capturing module 70 is configured to receive the light pattern of the test pattern focused by the collimator unit 60.

According to this, the light source module 30, the diffusion sheet 40, the pattern test card 50, the collimator unit 60, and the image capturing module 70 are sequentially arranged, so that the lens 20 to be tested and the pattern test card 50 are arranged. Under the condition of the micro-distance D, the optically-determined modulation transfer function (MTF) can be detected on the lens 20 to be measured. Therefore, the installation space requirement of the lens detection device is small. Because the micro-distance between the surface 21 of the lens 20 to be tested and the light-emitting surface 51 of the pattern test card 50 is 25 mm, the light pattern of the test pattern generated by the pattern test card 50 passes through the lens 20 Then, the test pattern light pattern will be generated at the focal point corresponding to the image plane of the lens 20 (ie, on the focusing plane 231), and the present invention passes the test pattern of the lens 20 through the collimator unit 60. The light type (that is, imaging) is received and then projected to the image capturing module 70, and an infinite distance is simulated between the lens 20 to be measured and the image capturing module 70. Finally, the image capturing module 70 can be coupled Connected to a host (not shown in the figure), after obtaining the light pattern image of the test pattern, the host can use the image to obtain the corresponding optical characteristic value, such as MTF.

In addition, under the condition of the micro distance D between the lens to be tested 20 and the pattern test card 50, the MTF can be accurately measured on and off the axis, and the image acquisition module is on the axis. The image center point of 70, and the off-axis are other positions of the image of the image capturing module 70.

In addition, as shown in FIG. 3, a micro-distance lens detection device provided by a second embodiment of the present invention is also suitable for detecting the lens 20 to be measured at a micro-distance D. The micro-distance lens detection device also includes sequential settings. The light source module 30, the diffusion sheet 40, the pattern test card 50, the collimator unit 60, and the image capturing module 70 are different in that:

The focusing plane 231 of the lens 20 to be measured is located outside the lens barrel 22. According to this, the MTF measurement can be performed on the lens 20 under test regardless of whether the focusing plane 231 is inside the lens mechanism or outside the lens mechanism.

It is worth noting that, in another implementation state, please refer to FIG. 2 at the same time. The micro-distance lens detection device includes a light source module 30, a filter 80, a pattern test card 50, and a collimator, which are sequentially arranged. The unit 60 and an image capturing module 70, that is, the diffuser 40 is replaced with a filter 80, the difference is that the filter 80 is provided on the path of the light provided by the light source module 30, and is used for Filter out specific wavelengths of the light. The collimator unit 60 is changed according to the filter 80, and in particular the imaging lens 61. The pattern test card 50 is provided on the path of the filtered light and has a light emitting surface 51. The light pattern of the test pattern required by the lens 20 to be tested is generated by the light.

[Habitant]

11‧‧‧light source module

12‧‧‧ Pattern Test Card

13‧‧‧Image acquisition module

14‧‧‧lens

15‧‧‧Host

[this invention]

D‧‧‧ micro distance

20‧‧‧lens

21‧‧‧ surface

22‧‧‧ Mirror Tube

23‧‧‧ lens group

231‧‧‧Focus plane

30‧‧‧light source module

40‧‧‧ diffuser

50‧‧‧Pattern test card

51‧‧‧light surface

60‧‧‧collimator unit

61‧‧‧Image taking lens

62‧‧‧collimator

70‧‧‧Image acquisition module

80‧‧‧ Filter

FIG. 1 is a schematic diagram of a conventional lens detection device; FIG. 2 is a schematic diagram of a first embodiment of the present invention; and FIG. 3 is a schematic diagram of a second embodiment of the present invention.

Claims (10)

A micro-distance lens detection device is suitable for micro-distance detection of a lens to be tested with a surface. The micro-distance lens detection device includes a light source module, a diffusion sheet, a pattern test card, and A collimator unit and an image capturing module, wherein: the light source module provides a light; the diffusion sheet is provided on the path of the light to make the light passing through more uniform; the pattern test card, set On the path of the light after uniformity, there is a light emitting surface, and the light pattern of the test pattern required by the lens to be tested is generated by the light; the lens to be tested is set on the pattern test card and the collimator Between the units, and between the surface of the lens under test and the light emitting surface of the pattern test card, the micro distance is less than 25 mm; the collimator unit is used to receive the The light pattern of the test pattern is focused on the image capturing module; the image capturing module is used to receive the light pattern of the test pattern focused by the collimator unit. The micro-distance lens detection device according to claim 1, wherein the lens to be measured has a lens barrel and a plurality of lens groups disposed in the lens barrel, the lens group generates a focusing plane, and the focusing plane is located in the lens barrel Inside or outside the lens barrel. The micro-distance lens detection device according to claim 1, wherein the micro-distance is less than 10 mm. The micro-distance lens detection device according to claim 1, wherein the test pattern of the pattern test card is a bar chart, an edge chart, or a slit chart. The micro-lens detection device according to claim 1, wherein the collimator unit includes an imaging lens and a collimator, and the imaging lens is used to receive the test chart after passing through the lens to be tested Sample light type, the collimator is used to receive the light pattern of the test pattern passing through the image capturing lens and focus on the image capturing module. A micro-distance lens detection device is suitable for micro-distance detection of a lens to be tested with a surface. The micro-distance lens detection device includes a light source module, a filter, a pattern test card, A collimator unit and an image capturing module, wherein: the light source module provides a light; the filter is arranged on the path of the light to filter out a specific wavelength of the light; the pattern test The card is provided on the path of the filtered light and has a light emitting surface, and the light pattern of the test pattern required by the lens to be tested is generated by the light; the lens to be tested is provided on the pattern test card and The micro-distance is between the collimator unit and the surface of the lens to be tested and the light-emitting surface of the pattern test card, and the micro-distance is less than 25 mm; the collimator unit is used to receive the collimator. The light pattern of the test pattern after measuring the lens is focused on the image capturing module; the image capturing module is used to receive the light pattern of the test pattern focused by the collimator unit. The micro-distance lens detection device according to claim 6, wherein the lens to be measured has a lens barrel and a plurality of lens groups provided in the lens barrel, the lens group generates a focusing plane, and the focusing plane is located in the lens barrel Inside or outside the lens barrel. The micro-distance lens detection device according to claim 6, wherein the micro-distance is less than 10 mm. The micro-lens detection device according to claim 6, wherein the test pattern of the pattern test card is a bar chart, an edge chart, or a slit chart. The micro-lens detection device according to claim 6, wherein the collimator unit includes a collimator and an imaging lens, and the imaging lens is used to receive the light pattern of the test pattern after passing through the lens to be tested The collimator is used for receiving the light pattern of the test pattern passing through the image capturing lens and focusing on the image capturing module.