WO2019033624A1 - Microlens array inspection system and microlens array inspection method - Google Patents

Abstract

A microlens array inspection system (100, 200, and 300) and a microlens array inspection method. The microlens array inspection system (100, 200, and 300) comprises: a light source apparatus (110, 210, and 310), a microlens array to be inspected (120, 220, and 320), an optic stop (140), and a luminous flux testing apparatus. The light source apparatus (110, 210, and 310) is used for emitting a light. The microlens array to be inspected (120, 220, and 320) is used for receiving and transmitting the light. The optic stop (140) comprises an aperture having a preset diameter. The aperture is used for transmitting the light emitted by the microlens array to be inspected (120, 220, and 320). The luminous flux testing apparatus is used for testing respectively a first luminous flux prior to passing though the optic stop (140) and a second luminous flux after passing through the optic stop (140). The first luminous flux and the second luminous flux are used for analyzing the quality of the microlens array to be inspected (120, 220, and 230). The microlens array inspection system (100, 200, and 300) and the microlens array inspection method employing the microlens array inspection system (100, 200, and 300) are simple and efficient to operate and highly accurate.

Description

Microlens array detection system and microlens array detection method Technical field

The present invention relates to the field of microlens array technology, and in particular, to a microlens array detection system and a microlens array detection method.

Background technique

This section is intended to provide a context or context for the specific embodiments of the invention set forth in the claims. The description herein is not admitted to be prior art as it is included in this section.

At present, the commonly used processing techniques for microlens arrays are: photolithography, open mold casting, mechanical processing, and the like. Among them, the mode of mold opening is the preferred process due to the low cost. In the process of mold processing, the dimensional accuracy of the microlens unit near the edge will decrease, resulting in errors in the size and aspect ratio of the edge microlens unit. In the end, the image size and aspect ratio of the double compound eye are changed, and the optical efficiency is lowered. In the case of good detection of the compound eye device itself, since the microlens lens unit is small and large in number, the method of measuring the size of the microlens unit can hardly be realized efficiently and accurately.

Summary of the invention

In order to solve the technical problem of low detection efficiency and low accuracy of the prior art microlens array, the present invention provides a microlens array detection system capable of effectively improving detection efficiency and accuracy, and the present illumination also provides a microlens array. Detection method.

A microlens array detection system comprising:

a light source device for emitting light;

a microlens array to be tested for receiving and transmitting the light;

The aperture includes a light-passing aperture having a predetermined aperture for transmitting light emitted by the array of microlenses to be tested;

a luminous flux testing device for respectively testing a first luminous flux before passing the light through the pupil and a second luminous flux passing through the aperture, the first luminous flux and the second luminous flux Luminous flux is used to analyze the quality of the microlens array to be tested.

Further, the microlens array detecting system further includes an analyzing device, configured to analyze a quality of the microlens array to be tested according to a ratio of the second luminous flux and the first luminous flux.

Further, the microlens array detection system further includes a relay device disposed between the microlens array to be tested and the aperture for concentrating light emitted from the microlens array to be tested to the The aperture of the aperture.

Further, the light source device comprises a laser and a beam expanding device, wherein the beam expanding device is configured to increase a divergence angle of the laser beam emitted by the laser, so that the light emitted by the light source device can illuminate the microlens array to be tested. A larger range of light apertures.

Further, the beam expanding device is a diffusion sheet.

Further, the distance L between the beam expanding device and the microlens array to be tested satisfies:

L=H/2tan(θ)

The difference between the diameter of the spot on the microlens array to be tested and the clear aperture H of the microlens array to be tested falls within a first preset error range.

among them,

Θ≤arcsin(1/2F#)

F#=F/d

θ is the divergence angle of the light emitted by the light source device, F is the focal length of the microlens array to be tested, and d is the diameter of each microlens on the microlens array to be tested.

Further, the beam expanding device includes a concave lens and a convex lens, and the laser beam sequentially passes through the concave lens and the convex lens to obtain the light.

Further, a focal length f1 of the concave lens and a focal length f2 of the convex lens satisfy:

F1/f2=h/H

The difference between the diameter of the spot on the microlens array to be tested and the aperture of the microlens array to be tested falls within a first predetermined error range, where h is the diameter of the laser beam, H The height of the aperture of the microlens array to be tested.

Further, the beam expanding device comprises a beam expanding microlens array, and the aperture diameter difference between the beam expanding microlens array and the microlens array to be tested falls within a second preset error range.

Further, the expanded beam microlens array is a single fly-eye lens.

A microlens array detecting method, wherein the microlens array detecting system according to any one of the preceding claims, wherein the ratio of the second luminous flux to the first luminous flux is greater than or equal to a proportional threshold, the microlens array to be tested qualified.

The present invention provides a microlens array detection system and a microlens array detection method. The microlens array detection system emits light through the light source device, and the light passes through the microlens array to be tested and the aperture, and then exits. Detecting the quality of the microlens array to be tested by the first luminous flux before the pupil and the second luminous flux after the aperture, the microlens array detection system and the detection of the microlens array using the microlens array detection system The method is simple and efficient, and the accuracy is high.

DRAWINGS

FIG. 1 is a schematic structural diagram of a microlens array detecting system according to a first embodiment of the present invention.

2 is a schematic view of a spot formed when the emitted light of the microlens array to be tested includes stray light as shown in FIG. 1.

FIG. 3 is a schematic structural diagram of a microlens array detecting system according to a second embodiment of the present invention.

FIG. 4 is a schematic structural diagram of a microlens array detecting system according to a third embodiment of the present invention.

Main component symbol description

Microlens array detection system	100, 200, 300
Light source device	110, 210, 310
illuminator	111, 211, 311
Beam expander	112, 212, 312
Microlens array to be tested	120, 220, 320
concave lens	212a
Convex lens	212b
Relay device	130

Light	140
Edge spot	a

The invention will be further illustrated by the following detailed description in conjunction with the accompanying drawings.

Detailed ways

Please refer to FIG. 1 , which is a schematic structural diagram of a microlens array detection system 100 according to a first embodiment of the present invention. The microlens array detection system 100 includes a light source device 110, a microlens array 120 to be tested, a relay device 130, an aperture 140, a luminous flux test device (not shown), and an analysis device (not shown). The light source device 110 is configured to emit light; the microlens array 120 to be tested is configured to receive and transmit the light; the relay device 130 is disposed between the microlens array 120 to be tested and the aperture 140. The light emitted from the microlens array 120 to be tested is concentrated to the light passing hole of the aperture 140; the diaphragm 140 includes a light passing hole having a predetermined aperture for transmitting The light emitted from the microlens array 120; the luminous flux testing device is configured to respectively test the first light flux η1 before the light passes through the aperture 140 and the second light flux η2 after passing through the aperture 140; the analyzing device And configured to analyze the quality of the microlens array 120 to be tested according to the first luminous flux η1 and the second luminous flux η2 to determine whether the dimensional consistency of the microlens unit on the microlens array 120 to be tested is qualified.

Specifically, the light source device 110 includes an illuminant 111 and a beam expanding device 112. The light source device 110 may be a blue light source that emits blue light. It is to be understood that in other embodiments, the light source device may be a white light source, a violet light source, or the like, and is not limited thereto. The illuminant 111 is a blue laser for emitting a blue laser as the ray. Specifically, the number of the illuminants 111 can be selected according to actual needs.

The beam expanding device 112 is configured to increase a divergence angle of the laser beam emitted by the illuminant 111, so that the light emitted by the light source device 110 can illuminate a larger range of the aperture of the microlens array 120 to be tested. In this embodiment, the beam expanding device 112 is a diffusing sheet.

In this embodiment, the microlens array 120 to be tested is a double fly-eye lens, and the double fly-eye lens has a broad application prospect in the field of microdisplay and projection display because of high light energy utilization rate and uniform illumination of a large area. The double fly-eye lens includes a light incident side and a light exit side, The light incident side and the light exit side are both provided with a microlens array, and the light exiting side microlens array is located on a focal plane of the light incident side microlens array.

Further, the double-folding eye lens for homogenization itself has a certain requirement for the incident light divergence angle, that is, the incident light divergence angle matches the F# of the double fly-eye lens itself,

Θ≤arcsin(1/2F#)

F#=F/d

θ is the divergence angle of the light emitted by the light source device 110, F is the focal length of the microlens array 120 to be tested, and d is the diameter of each microlens on the microlens array 120 to be tested.

In addition, the distance L between the beam expanding device 112 and the microlens array 120 to be tested satisfies:

L=H/2tan(θ)

The difference between the spot diameter of the light source device 110 and the light path diameter H of the microlens array 120 to be tested falls within a preset error range, so that the spot diameter and the spot diameter The apertures H are substantially the same to obtain more accurate detection results. At this time, the microlens unit detected on the microlens array 120 to be tested is sufficiently large and the light does not generate stray light through the microlens array 120 to be tested. FIG. 2 is a light spot formed when the light to be detected by the microlens array 120 to be tested shown in FIG. 1 includes stray light. The spot in Fig. 2 includes four edge spots a formed by the stray light, the edge spot a being weaker relative to the middle portion of the entire spot. When the size of the microlens array 120 to be tested has an error, the light image emitted by the microlens array 120 to be tested is also shown in FIG. 2.

The relay device 130 guides the light emitted from the microlens array 120 to be measured to the light passing hole of the aperture 140. In this embodiment, the relay device 130 is a concentrated plano-convex lens for incident light.

The aperture 140 is a field stop and the luminous flux that can pass through the aperture 140 will be an effective luminous flux. The light-passing aperture of the aperture 140 has a predetermined aperture. When the quality of the microlens array 120 to be tested is good, that is, the shape and size of the microlens array 120 to be tested are consistent, and the image quality is good, the output light is in the light. The spot size formed at the crucible 140 is exactly the same as the preset aperture size, and the energy of the spot before and after the aperture 140 is not lost, the first luminous flux η1 is equal to the second luminous flux η2; when the microlens array to be tested 120 quality When the image is inferior, that is, the shape of the microlens array 120 to be tested is inferior in shape consistency, and when the image quality is poor, the size of the spot formed by the output light at the stop 140 is inconsistent with the preset aperture, and passes through the aperture 140. The energy loss of the spot is large, and the first luminous flux η1 and the second luminous flux η2 are largely different.

The luminous flux testing device is configured to test a first luminous flux η1 before the light passes through the aperture 140 and a second luminous flux η2 after passing through the aperture 140 to measure the light passing through the aperture 140. Can lose the situation. It can be understood that the luminous flux testing device can be an optical power meter for testing optical power or a luminance meter for detecting light brightness.

The analysis device stores a proportional threshold input by the user and is used to calculate a ratio of the second luminous flux η2 to the first luminous flux η1. The analyzing device compares the ratio τ with the proportional threshold, when the ratio τ is greater than or equal to the proportional threshold, the microlens array 120 to be tested is qualified; when the ratio τ is less than the proportional threshold The quality of the microlens array 120 to be tested is unqualified. In the case where the number of microlens arrays 120 to be tested is large, the analysis device can improve detection efficiency and accuracy.

The microlens array detection system in the first embodiment of the present invention emits light through the light source device 110, and the light passes through the microlens array 120 to be tested and the aperture 140, and is emitted according to the front of the aperture 140. A light flux η1 and a second light flux η2 after the aperture 140 are used to analyze the quality of the microlens array 120 to be tested, and the operation is simple and efficient, and the accuracy is high.

The first embodiment of the present invention further provides a method for detecting a microlens array. The microlens array detection system 100 includes the following steps:

S1: turning on the light source device 110, the light source device 110 emitting light that is irradiated to the microlens array 120 to be tested;

S2: using the luminous flux testing device to measure the first luminous flux η1 before obtaining the aperture 140;

S3: measuring, by the luminous flux testing device, the second luminous flux η2 after obtaining the aperture 140;

S4: if a ratio of the second luminous flux η2 to the first luminous flux η1 is greater than or equal to The microlens array 120 is qualified; if the ratio of the second luminous flux η2 to the first luminous flux η1 is less than the proportional threshold, the microlens array 120 to be tested is unqualified;

S5: distinguish the unqualified microlens array 120 to be tested from other microlens arrays 120 to be tested.

The detection method of the microlens array provided by the first embodiment of the present invention is simple and efficient in operation and high in accuracy.

Please refer to FIG. 3 , which is a schematic structural diagram of a microlens array detection system 200 according to a second embodiment of the present invention. The main difference between the microlens array detection system 200 and the microlens array detection system 100 in this embodiment is that the microlens array detection system 200 includes a light source device 210, wherein the light source device 210 is provided with an illuminant 211 and a beam expander 212. The beam expanding device 212 is different in structure from the beam expanding device 112. Other components in the microlens array detection system 200 are the same as those in the microlens array detection system 100, and are not described herein.

The beam expander 212 includes a concave lens 212a and a convex lens 212b. The laser beam emitted by the illuminant 211 sequentially passes through the concave lens 212a and the convex lens 212b to obtain light emitted by the light source device 210. After the laser beam passes through the beam expanding device 212, the beam diameter increases, and the spot incident on the microlens array 220 to be tested is a Gaussian distribution spot. The beam expanding device 212 controls the beam diameter change accurately, and can avoid incidence. The divergence angle of the light beam to the microlens array 220 to be tested is too large to cause the microlens array 220 to be tested to emit stray light. The distance between the beam expanding device 212 and the microlens array 220 to be tested can be flexibly adjusted in a wide range, which is advantageous for the construction of the microlens array detecting system 200.

Specifically, the focal length f1 of the concave lens 212a and the focal length f2 of the convex lens 212b satisfy:

F1/f2=h/H

The difference between the diameter of the spot on the microlens array 220 to be tested and the clear aperture H of the microlens array 220 to be tested falls within a preset error range, such that the spot diameter and the clear aperture H is roughly the same to obtain more accurate test results. Its Where h is the diameter of the laser beam emitted by the illuminant 211, and H is the height of the aperture of the microlens array 220 to be tested.

The second embodiment of the present invention is the same as the first embodiment. The microlens array detection system 200 has a simple structure, and analyzes the quality of the microlens array 120 to be tested according to the first luminous flux η1 and the second luminous flux η2. The operation is simple and efficient. The accuracy is high.

Please refer to FIG. 4 , which is a schematic structural diagram of a microlens array detection system 300 according to a third embodiment of the present invention. The main difference between the microlens array detection system 300 and the microlens array detection system 100 in this embodiment is that the microlens array detection system 300 includes a light source device 310, wherein the light source device 310 is provided with an illuminant 311 and a beam expander 312, the beam expanding device 312 is different in structure from the beam expanding device 112. Other components in the microlens array detection system 300 are the same as those in the microlens array detection system 100, and are not described herein.

Specifically, the beam expanding device 312 includes a beam expanding microlens array, and a difference between the beam expanding aperture of the beam expanding microlens array and the microlens array 320 to be tested falls within a preset error range, so that the beam expanding The aperture ratio of the microlens array to the microlens array 320 to be tested is substantially the same to obtain a more accurate detection result. In this embodiment, the expanded beam microlens array is a single compound eye microlens. The Gaussian-distributed laser beam emitted by the illuminant 311 passes through the single compound eye microlens and exits and forms a uniform rectangular spot on the microlens array 320 to be tested. The rectangular spot is matched in size to the microlens array 320 to be tested. The beam expanding device 312 uses a small number of optical components, and the distance between the microlens array 320 and the microlens array 320 to be tested can be flexibly adjusted in a wide range, which is advantageous for the construction of the microlens array detecting system 300.

The third embodiment of the present invention is the same as the first embodiment. The microlens array detection system 300 has a simple structure, and analyzes the quality of the microlens array 320 to be tested according to the first luminous flux η1 and the second luminous flux η2, and the operation is simple and efficient. The accuracy is high.

The above is only the embodiment of the present invention, and is not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformations made by the description of the invention and the drawings are directly or indirectly applied to other related technologies. The fields are all included in the scope of patent protection of the present invention.

Claims (11)

1. A microlens array detection system, comprising:

   a light source device for emitting light;

   a microlens array to be tested for receiving and transmitting the light;

   The aperture includes a light-passing aperture having a predetermined aperture for transmitting light emitted by the array of microlenses to be tested;

   The luminous flux testing device is configured to respectively test a first luminous flux of the light before passing through the aperture and a second luminous flux after passing through the aperture, the first luminous flux and the second luminous flux being used for analyzing a microlens to be tested The quality of the array.
2. The microlens array detecting system according to claim 1, wherein said microlens array detecting system further comprises analyzing means, said analyzing means analyzing said to be measured based on a ratio of said second luminous flux to said first luminous flux The quality of the microlens array.
3. The microlens array detection system according to claim 1, wherein the microlens array detection system further comprises a relay device, the relay device being disposed between the microlens array to be tested and the aperture. The light for emitting the array of microlenses to be tested is concentrated to the light-passing holes of the aperture.
4. A microlens array detecting system according to claim 1, wherein said light source means comprises a laser and a beam expanding means for increasing a divergence angle of a laser beam emitted from said laser, such that said The light emitted by the light source device can illuminate a larger range of the aperture of the microlens array to be tested.
5. A microlens array detecting system according to claim 4, wherein said beam expanding means is a diffusion sheet.
6. The microlens array detecting system according to claim 5, wherein a distance L between the beam expanding device and the microlens array to be tested satisfies:

   L=H/2tan(θ)

   The difference between the diameter of the spot on the microlens array to be tested and the clear aperture H of the microlens array to be tested falls within a first preset error range.

   among them,

   Θ≤arcsin(1/2F#)

   F#=F/d

   θ is the divergence angle of the light emitted by the light source device, F is the focal length of the microlens array to be tested, and d is the diameter of each microlens on the microlens array to be tested.
7. The microlens array detecting system according to claim 4, wherein said beam expanding means comprises a concave lens and a convex lens, said laser beam sequentially passing through said concave lens and said convex lens to obtain said light.
8. The microlens array detecting system according to claim 7, wherein a focal length f1 of the concave lens and a focal length f2 of the convex lens satisfy:

   F1/f2=h/H

   The difference between the diameter of the spot on the microlens array to be tested and the aperture of the microlens array to be tested falls within a first predetermined error range, where h is the diameter of the laser beam, H The height of the aperture of the microlens array to be tested.
9. The microlens array detecting system according to claim 4, wherein the beam expanding device comprises a beam expanding microlens array, and a difference between the beam expanding microlens array and the aperture of the microlens array to be tested falls Within the second preset error range.
10. A microlens array detecting system according to claim 9, wherein said beam expanding microlens array is a single fly-eye lens.
11. A microlens array detecting method according to any one of claims 1 to 10, wherein a ratio of the second luminous flux to the first luminous flux is greater than or equal to a proportional threshold , the microlens array to be tested is qualified.

Images