WO2019159427A1

WO2019159427A1 - Camera module adjustment device and camera module adjustment method

Info

Publication number: WO2019159427A1
Application number: PCT/JP2018/037710
Authority: WO
Inventors: 啓一本屋; 務大下
Original assignee: 株式会社カツラ・オプト・システムズ
Priority date: 2018-02-13
Filing date: 2018-10-10
Publication date: 2019-08-22
Also published as: JP6729960B2; JPWO2019159427A1; TW201935058A

Abstract

[Problem] To provide a camera module adjustment device and a camera module adjustment method, wherein when adjusting the distance between a camera module lens and an image capturing element, the image capturing element is driven and an image of a test chart is not captured. [Solution] According to the present invention, a light spot, on which parallel light beams are focused by a lens of a camera module, is formed on an image capturing element of the camera module. An image signal is generated by an image capturing element of an image capturing unit by being photoelectrically converted from a light spot on which parallel light beams are focused by a collimator lens of the image capturing unit, wherein the parallel light beams are converted, from the light reflected by the light spot in the image capturing element, to be approximately parallel by means of a lens. An adjustment of the camera module is performed on the basis of the distance between the image capturing element and the lens of the camera module, said distance being determined on the basis of a focus evaluation value calculated for the light spot on the basis of the image signal.

Description

Camera module adjustment apparatus and camera module adjustment method

The present invention relates to a camera module adjustment device and a camera module adjustment method.

2. Description of the Related Art Conventionally, in an image input device manufacturing process such as a camera module, focus adjustment between an image sensor and a lens unit composed of a CCD (Charge Coupled Devices), a CMOS (Complementary Metal Oxide Semiconductor), or the like has been performed.

A camera module is a component in which a substrate on which an image sensor is mounted and an imaging lens unit are integrated, and it is a digital camera as well as various portable electronic devices with a camera function (for example, a mobile phone, a mobile phone, etc.). Type PC, PDA, etc.). When manufacturing a camera module, it is known to hold the lens unit while adjusting the focus on the imaging surface of the image sensor, and to fix the lens unit and the substrate together as the focus is adjusted. ing.

With regard to such a technique, for example, JP-A-2003-315650 (Patent Document 1) and JP-A-2002-267923 (Patent Document 2) use a test chart (chart paper) having a chart portion. A technique for detecting an optimum focus position by capturing a test chart while moving the lens unit and calculating MTF (Modulation Transfer Function) from the captured data is disclosed.

In order to inspect the characteristics of the camera module, an AF lens unit characteristic inspection apparatus as disclosed in JP 2012-149928 A (Patent Document 3) is known. Patent Document 3 discloses an AF driving device having a driving unit such as a VCM (voice coil motor) or a stepping motor for moving the position of an imaging lens of an AF (autofocus) lens unit to be inspected, and an AF lens. A measurement lens disposed on the upper side of the unit 1, a measurement sensor as an imaging sensor disposed on the upper side of the AF lens unit, a reference chart disposed on the lower side of the AF lens unit, and a measurement Based on image data of the reference chart from the sensor, an AF driving device that calculates the MTF (for example, optical characteristics and resolution of the lens) for the input current value to the AF lens unit 1 and inspects the resolution of the measurement lens An AF lens unit characteristic inspection apparatus including an AF drive control circuit for controlling AF drive is disclosed. . In addition, the AF lens unit characteristic inspection apparatus described in Patent Document 3 allows light such as a halogen lamp to enter through a reference chart, and causes the imaging sensor to detect a light spot (image data) emitted from the imaging lens. . Then, the MTF calculation device calculates the input current value−MTF value based on the image data from the measurement sensor corresponding to the input current value from the AF drive control circuit, and the MTF peak value sets the reference value (threshold value). The resolution of the lens can be inspected depending on whether or not it exceeds.

Further, Japanese Patent Laid-Open No. 2010-021985 (Patent Document 4) discloses a chart unit, a collector unit, and a collector unit for adjusting the position of the element unit with respect to the photographing lens (lens unit) and fixing the element unit to the lens unit after adjustment. There is disclosed a camera module manufacturing apparatus that includes an optical unit, a lens positioning plate, a lens holding mechanism, an element moving mechanism, an adhesive supplier, an ultraviolet lamp, and a control unit that controls them.

Here, an example of a schematic diagram of a conventional camera module adjustment apparatus 100 is shown in FIG. As shown in FIG. 1, in the camera module adjustment apparatus 100, the chart image is illuminated by a transmissive chart (test chart, pattern) 102 using an illumination unit 101.

The chart image reflected by the half mirror 103 is converted into parallel rays by a collimator lens (collimation lens) 104 and enters the camera module 105. Further, the chart image is formed on the image sensor 105 b by the lens 105 a of the camera module 105.

Next, the chart image on the image sensor 105b is converted into an electric signal by the image sensor 105b, and the electric signal is input to the control unit 106 (for example, a computer). And the control part 106 converts the electric signal into digital data, and displays it on the display part 106a (for example, monitor).

Finally, an operator (inspector) inspecting the camera module 105 adjusts the distance between the lens 105a of the camera module 105 and the image sensor 105b so that the display unit 106a is in focus.

The camera module adjustment apparatus 100 has an autocollimator function by using the image sensor 107 and the collimator lens 104 that can observe the camera module. Then, by displaying the output of the image sensor 107 on a monitor (not shown), it is possible to adjust the angle of irradiation light irradiated to the camera module, set conditions, and the like.

JP 2003-315650 A JP 2002-267923 A JP 2012-149928 A JP 2010-021985

In the conventional camera module adjustment apparatus and camera module adjustment method, it was necessary to image a test chart (for example, chart paper) using the image sensor of the camera module to be adjusted. In addition, the display unit needs to display a test chart image using an electrical signal obtained by converting a test chart captured by the image sensor.

Furthermore, in recent years, wide-angle lenses or fish-eye lenses tend to be employed as lenses in camera modules. With this trend, it has become necessary to adjust the distance (focus) between the lens and the image sensor in the camera module having a high image height. In the present specification, “image height” is an index indicating the height of the image from the center of the captured image. In other words, the “image height” is the distance (distance) between the edge of the image (eg, the peripheral part, the position farthest from the image center) and the center of the image in the direction perpendicular to the optical axis of the camera module. Point to.

Also, mass-produced camera modules used for mobile phones and the like must produce a large number of products that satisfy a certain quality in a short time. However, it is considered difficult to apply the inventions described in Patent Documents 1 to 4 to manufacture a low-cost mass-produced camera module.

The present invention has been made under the circumstances as described above, and an object of the present invention is to drive an image sensor to capture an image of a test chart when adjusting the distance between the lens of the camera module and the image sensor. It is an object of the present invention to provide a camera module adjustment apparatus and a camera module adjustment method that do not have any.

In particular, a camera module adjustment device and a camera module adjustment method for a camera module that can adjust the distance between the lens and the imaging element in a camera module in which a wide-angle lens (including a fisheye lens) is used as a lens. There is.

The object of the camera module adjustment device according to the present invention is a camera module adjustment device having a light source unit, a camera module, a photographing unit, and a control unit, wherein the light source unit is a light source and outputs light emitted from the light source. And a first collimator lens that converts the first light incident from the pinhole into a first parallel light beam, and the pinhole includes the first collimator lens. The first collimator lens is disposed at a position approximately away from the focal length of the first collimator lens, and the camera module forms a first light spot on which the first parallel light beam is condensed by the lens and the lens. The first imaging element, wherein the imaging unit has converted the second light reflected by the first imaging element into substantially parallel by the lens. A second collimator lens that condenses the two parallel rays, and a second imaging device that generates an image signal obtained by photoelectrically converting the second light spot collected by the second collimator lens, and the control The unit includes a calculation unit that calculates a focus evaluation value for the second light spot based on the image signal, and a display unit that displays the second light spot, and the control unit includes: A distance between the lens and the first image sensor along a direction perpendicular to the light receiving surface of the first image sensor is determined based on a focus evaluation value, and the camera module is determined based on the distance. This is achieved by making adjustments.

According to another aspect of the present invention, there is provided a camera module adjustment device, wherein the camera module includes a lens holding unit that holds the lens, the lens holding unit is moved in the direction, and the lens is based on the distance. By providing a lens holding and moving unit that moves the holding unit to the camera module adjustment position, or by deflecting the first parallel light beam and irradiating the camera module, without deflecting the second parallel light beam. By providing a straight beam splitter, or the beam splitter is a half mirror or a non-deflection beam splitter, or the lens is a wide-angle lens or a fish-eye lens, and the second light is the first image sensor. By reflecting with a reflection type diffraction grating on the light receiving surface, or the camera module To fix the integer position, the ultraviolet curable resin is applied in a gap between the said lens holding portion first imaging element, by irradiating ultraviolet rays to the ultraviolet curing resin is more effectively achieved.

The object of the camera module adjustment method according to the present invention is a camera module adjustment method including a light source unit, a camera module, a photographing unit, a control unit, and a lens holding and driving unit, wherein the light source unit is a pinhole. The light emitted from the light source is converted into the first light, the first collimator lens converts the first light incident from the pinhole into the first parallel light beam, and the pinhole is The first collimated lens is disposed at a position substantially away from the collimator lens by the focal length of the first collimator lens, and the first parallel light beam is condensed on the light receiving surface of the first image sensor of the camera module by the lens of the camera module. The first light spot thus formed is formed on the first image sensor, and the photographing unit has the second light reflected by the first image sensor on the first light spot. The second collimated light beam converted into substantially parallel by the lens is condensed on the second image sensor by the second collimator lens, and the second light spot condensed by the second collimator lens is collected. The second imaging element generates a photoelectrically converted image signal, and the control unit calculates a focus evaluation value for the second light spot based on the image signal by the calculation unit, The display unit displays the second light spot, and the control unit, based on the focus evaluation value, the lens along the direction perpendicular to the light receiving surface of the first image sensor and the first This is achieved by determining the distance from the image pickup device and adjusting the camera module based on the distance.

In the camera module adjustment method according to the present invention, in the camera module, the lens holding unit holds the lens, the lens holding unit is moved in the direction, and the lens holding unit driving unit moves the distance. Based on the above, by moving the lens holding unit to the camera module adjustment position or by a beam splitter, the first parallel light beam is deflected to irradiate the camera module, and the second parallel light beam is By moving straight without deflecting, or when the beam splitter is a half mirror or a non-deflecting beam splitter, or the lens is a wide-angle lens or a fisheye lens, and the second light is the first imaging element By reflecting the light from the reflection type diffraction grating on the light receiving surface, or the camera module. In order to fix the lens adjustment position, an ultraviolet effect resin is applied to the gap between the lens holding portion and the first tsuzo element, and the ultraviolet curable resin is irradiated with ultraviolet rays, which is achieved more effectively. .

According to the camera module adjustment device and the camera module adjustment method according to the present invention, when adjusting the distance between the lens of the camera module and the image pickup device, it is not necessary to drive the image pickup device and image the test chart. An excellent effect can be achieved.

It is a schematic diagram of the conventional camera module adjustment apparatus. It is a schematic diagram of one Embodiment of the camera module adjustment apparatus which concerns on this invention. It is a figure which shows the specific example of the image by which the pixel of the image pick-up element of the camera module was imaged. It is a flowchart which shows the process which the camera module adjustment apparatus which concerns on this invention performs. It is a figure which shows the light beam path | route of another embodiment of the camera module adjustment apparatus which concerns on this invention. It is a figure which shows the mode of diffraction of the 1st-order diffracted light (m = 1) in the light-receiving surface of an image pick-up element in another embodiment of the camera module adjustment apparatus which concerns on this invention. It is a figure which shows the mode of diffraction of the diffracted light (m <0) in the light-receiving surface of an image pick-up element in another embodiment of the camera module adjustment apparatus which concerns on this invention. It is a figure which shows the mode of diffraction of the diffracted light (m '<0) in the light-receiving surface of an image pick-up element in another embodiment of the camera module adjustment apparatus which concerns on this invention.

In the camera module adjustment device and the camera module adjustment method according to the present invention, the light incident from the light source through the pinhole is converted into parallel rays by the collimator lens, and the parallel rays are condensed by the lens of the camera module lens. A light spot is formed on the image pickup device of the camera module, and the light reflected by the image pickup device is converted into a substantially parallel parallel light beam by the lens, and the parallel light beam is collected by the collimator lens of the photographing unit. An image signal obtained by photoelectrically converting the light spot is generated by the imaging device of the photographing unit, and based on the image signal, the focus evaluation value obtained by calculating the focus evaluation value for the light spot is determined. By adjusting the camera module based on the distance between the image sensor and the lens, the camera By driving the imaging element of La module, it has excellent effect that it is possible to perform the camera module adjustment without steps to image a test chart obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. A schematic diagram of a camera module adjustment device of a camera module according to an embodiment of the present invention is shown in FIG. In the embodiment of the present invention, the optical axis direction of the camera module 15 is set as the Z axis. The X-axis is provided in a direction perpendicular to the Z-axis, and the Y-axis is a direction perpendicular to the X-axis and the Z-axis, that is, a direction perpendicular to the paper surface (for example, a direction perpendicular from the top to the bottom of the paper surface). ).

First, in the camera module adjustment device 10 of the camera module 15, by providing a pinhole (through hole) 12 on the emission side of the light source 11, a light source that emits a light beam having an image height is obtained. The light beam that has passed through the pinhole 12 is converted into a parallel light beam by a collimator lens 13 having a focal length f ₁ . Further, the parallel light beam reflected by the half mirror 14 enters the camera module 15.

In addition, the camera module 15 includes a lens 15a having a focal length f _2, and the image pickup device 15b that are spaced apart at a point approximately the focal length f ₂ from the lens 15a, a lens holding portion 15c for holding the lens 15a It is configured. A plurality of pixels are arranged in a matrix on the light receiving surface of the image sensor 15b.

The parallel light rays incident on the camera module 15 are imaged as light spots on the light receiving surface of the image sensor 15b by the lens 15a. Subsequently, the light spot is reflected by the light receiving surface of the image sensor 15b and converted into parallel rays again by the lens 15a. The parallel rays pass through the half mirror 14 and form an image as a light spot on the image sensor 17 by the lens collimator 16 having the focal length f ₃ .

Next, the image sensor 17 outputs an image signal obtained by photoelectrically converting the image of the light spot to the control unit 18. And the calculating part 18a of the control part 18 memorize | stores the focus evaluation value calculated based on the image signal. The in-focus evaluation value is a numerical value indicating the degree to which the lens 15a is focused (focused) on the image sensor 15b.

Next, the calculation unit 18 b of the control unit 18 outputs the movement amount of the lens holding unit to the driving unit 19 a of the lens holding driving unit 19.

Then, the driving unit 19a moves the lens holding and coupling unit 19b along the Z-axis direction (direction perpendicular to the light receiving surface of the image sensor 15b) based on the movement amount. Since the lens holding unit 15c is coupled to the lens holding coupling unit 19b, the lens holding unit 15b moves in the Z-axis direction in conjunction with the movement amount of the lens holding coupling unit 19b.

Here, in the camera module adjustment process of the camera module 15, when the lens 15a is focused on the image sensor 15b, the state of the light spot imaged by the image sensor 17 is shown in FIG. FIG. 3 shows a state in which a plurality of pixels arranged on the light receiving surface of the image sensor 15b are arranged in a matrix.

The image of the pixel of the image sensor 15b and the reflected image formed on a window glass (for example, a filter, a protective film, or a protective layer) disposed between the lens 15a of the camera module 15 and the image sensor. Can be clearly identified.

In particular, when the light beam incident on the pinhole 12 is a coherent light beam (for example, a laser beam), the light imaged by the image sensor 17 due to the diffraction phenomenon caused by the interval between the pixels of the image sensor 15b. The image of the pixel of the image sensor 15b is formed more clearly in the spot. Note that it is preferable that the diameter (hole) of the pinhole 12 is designed so that, when an image is formed on the light receiving surface of the image sensor 17, light rays are irradiated to a plurality of pixels of the image sensor 15 b. The reason is that when the diameter (width) of the light beam is equal to or smaller than the pixel size of the image sensor 15b, the irradiation position of the light beam changes the diffraction of the reflected light, and as a result, the image of the pixel inside the light spot is unstable. Because it becomes.

Next, a method for calculating the diameter of the light spot caused by the pinhole image will be described.

First, the diameter of the hole of the pinhole 12 is φ _a , and the diameter of the light spot on the light receiving surface of the image sensor 15 _b is φ _b . The focal length of the collimator lens 13 is f ₁ and the focal length of the lens 15b is f ₂ .

φ _b can be expressed as follows:

Further, the diameter of the light spot on the light receiving surface of the image sensor 17 is φ _c , the focal length of the collimator lens 16 on the imaging side is f _3, and φ _c can be expressed as shown in Equation 2.

Further, the distance between adjacent pixels of the image sensor 15b is d, and the size of the pixel image of the image sensor 15b formed on the light receiving surface of the image sensor 17 is d '. Can be expressed as

For example, the diameter φa of the pinhole 12 of the camera module (inspection target) 15 is 1.0 [mm], the focal length f ₁ of the collimator lens 13 on the light source side is 27 [mm], and the focal length f _{2 of the} lens is 2.5 [mm], the focal length f ₃ of the collimator lens 16 on the imaging side is 27 [mm], the pixel interval 5 [μm] of the imaging element 15b of the camera module 15, and the diameter of the light spot of the captured image, that is, φ _{b is set} to 92 [μm] (0.092 [mm]).

Based on these settings, the diameter φ _c of the light spot imaged by the image sensor 17 can be estimated as 994 [μm] (0.994 [mm]) from Equation 2.

Then, by the collimator lens 13, the light obtained by reducing the width of the light of the pinhole diameter phi _a, is focused as a light spot on the image sensor surface of the camera module. Further, the collimator lens 16 can enlarge the light spot on the light receiving surface of the image sensor 17.

Thus, the cell image of the light receiving surface of the image sensor 17 can be observed on the display unit (monitor) 18b.

Next, the camera module adjustment process performed by the camera module adjustment apparatus 10 will be described with reference to the flowchart of FIG.

First, the camera module adjustment device 10 is initialized (step S11). Next, the camera module 15 is installed at a predetermined position with respect to the camera module adjustment device (step S12).

Then, the light source 11 is turned on to irradiate the camera module 15 with light rays (step S13).

Next, the control unit 18 takes in the light spot on which the pinhole image is formed on the light receiving surface of the image sensor 15b of the camera module 15 by using the image sensor 17 (step S14). Then, the lens holding / driving unit 19 moves the lens holding unit 15 by a distance corresponding to a predetermined moving distance ΔD (step S15).

Next, it is determined whether or not the movement distance of the lens holding portion 15 in the Z-axis direction has reached a predetermined maximum distance Dmax (step S16).

If it is determined NO in step S16, the process returns to step S14. If the determination is Yes in step S16, the process proceeds to step S17 described later.

Next, the calculation unit 18a of the control unit 18 determines the distance (focal length) between the lens 15a and the image sensor 15b of the module 15 based on the relationship between the moving distance and the focus evaluation value (step S17).

And the control part 18 moves the lens holding part 15c to a camera module adjustment position (focus position) using the lens holding drive part 19 (step S18).

Next, an adhesive is applied between the lens holding portion 15c and the image sensor 15b (step S19). And an ultraviolet-ray is irradiated to an adhesive agent and an adhesive agent (ultraviolet curable resin) is hardened (step S20).

Finally, the camera module 15 is taken out (step S21).

Next, another embodiment of the present invention will be described.

Another embodiment of the present invention is a camera module adjustment device that can adjust the distance between a lens and an image sensor in a camera module in which the wide-angle lens 22 is used as a lens.

First, FIG. 5 is a schematic diagram showing a light beam path between a camera module in which the wide-angle lens 22 is used and a module adjustment device according to the present invention. As shown in FIG. 5, when focusing is performed on the light receiving surface of the image sensor 23 by the wide angle lens 22, the light incident on the wide angle lens 22 is received on the light receiving surface of the image sensor at a position where the image height of the lens is high. Because of reflection (regular reflection), the light does not enter the module adjustment device again and does not return to the module adjustment device side.

And on the light receiving surface of the image sensor 23, a plurality of pixels 23a are arranged in a lattice. Such a grating-like structure is a reflective diffraction grating structure. An image sensor 23 typified by a CCD image sensor or a CMOS image sensor has a reflective surface with a fine periodic structure. Due to such a structure, this reflecting surface acts in the same manner as a reflective diffraction grating.

First, when a light beam is incident at an incident angle θ _i with respect to the normal to the light receiving surface of the image sensor 23, most of the light beam is reflected as zero-order light at a reflection angle −θ _i . However, a part of the light beam is first-order diffracted at a diffraction angle θ _m as diffracted light, and the state of the light is shown in FIG.

Furthermore, high-order diffracted light is generated (generated) by reflected light that is periodically repeated in intensity.

Here, it is assumed that the diffraction order is m, the distance between adjacent pixels of the image sensor is d, and the wavelength of the light beam is λ. The diffracted light is diffracted from each pixel (marked surface) at a diffraction angle θ _m of the order m in accordance with the order m and the wavelength λ.

The relationship among the distance d, the wavelength λ, the order m, the incident angle θ _i , and the diffraction angle θ _m can be expressed as in Expression 4.

Here, the incident angle θ _i and the diffraction angle θ _m in Equation 4 will be described.

First, if incident light and diffracted light are on opposite sides of the surface normal of the image sensor 23, the incident angle θ _i is positive (plus), and the diffraction angle θ _m is negative (minus). To do. In addition, the incident angle θ _i and the diffraction angle θ _m are both positive (plus) if they are on the same side with respect to the surface normal of the image sensor 23.

In Equation 4, when m = 0, the reflection angle θ _{m = 0} is −θ _i without depending on the distance d and the wavelength λ.

Also, in Equation 4, the order m is an integer. That is, the order m is allowed to take values of 0, ± 1, ± 2,.

In the case of high-order diffracted light having a large order _m , it is considered that both the incident angle θ _i and the diffraction angle θ _m are allowed to be positive (plus). Then, when the incident angle θ _i and the diffraction angle θ _m are both positive (plus), it is considered that the higher-order diffracted light is diffracted in the direction in which the incident light is incident.

Here, FIG. 7 shows a state of reflection of the zero-order light and diffraction of the diffracted light (m <0) on the light receiving surface of the image sensor 23.

Further, by adjusting (optimizing) the wavelength λ of the light beam incident on the image sensor 23 of the camera module 21, the diffracted light of the order m ′ can be diffracted so as to return toward the camera module adjusting device 20. it is conceivable that.

However, in the case of an integer other than zero (m ≠ 0), the diffraction angle θ _m depends on the wavelength λ.

In order to utilize the wavelength dependency of the diffraction angle θm (λ), a white light source is suitable for the light source unit (not shown) of the camera module adjustment device 20.

In the embodiment of the present invention, the light beam reflected from the light spot formed on the light receiving surface of the image sensor of the camera module is detected using the image sensor of the camera module adjustment device, and the camera is adjusted so that the light spot is in focus. It has been explained that the camera module is adjusted so that the distance between the module lens and the image sensor is the same.

In order to evaluate the degree of focus of the light spot, it is preferable that the control unit of the camera module adjustment device calculates a focus evaluation value of the light spot.

As the focus evaluation value calculated by the control unit of the camera module adjustment device, for example, the contrast of the light spot may be used in addition to MTF (resolution, etc.) as described above.

Further, a contrast transfer function value (hereinafter referred to as CTF value) may be used as the focus evaluation value. The CTF value is a value representing the contrast of the image with respect to the spatial frequency of the light spot, and can be regarded as being in focus when the CTF value is high.

The present invention is not limited to the MTF value, resolution, or CTF value, and various evaluation methods and evaluation values that can evaluate the degree of focus can be used for measuring the focus position. . Further, the positional relationship between the lens of the camera module and the image sensor is adjusted only once, but may be repeated a plurality of times.

Further, in each of the above embodiments, the lens may be moved or the image sensor may be moved in adjusting the positional relationship between the lens of the camera module and the image sensor. Further, when the lens of the camera module is incorporated in a lens barrel or the like, the lens barrel itself may be moved to focus.

In the embodiment of the present invention, it has been shown that a parallel beam is deflected using a half mirror as a beam splitter. As the beam splitter, a cube type beam splitter or a plate type beam splitter may be used. In addition to the half mirror, for example, a prism or the like may be used.

10, 20, 100 Camera module adjustment device 11 Light source 12 Pinhole 13 Collimator lens 14

Half mirror

15, 21, 105 Camera module 15a Lens 15b Image sensor 15c Lens holding unit 16 Collimator lens 17 Image sensor 18 Control unit

18a Calculation unit

18b Display Unit 19 lens holding driving unit 19a driving unit 19b lens holding coupling unit 22 wide angle lens 23 imaging device 23a pixel 101 illumination unit 102 chart 103 half mirror 104 collimator lens 105a lens 105b imaging device 106 control unit 107 imaging device

Claims

A camera module adjustment device having a light source unit, a camera module, a photographing unit, and a control unit,
The light source unit includes a light source, a pinhole that converts light emitted from the light source into first light, and a first collimator that converts the first light incident from the pinhole into a first parallel light beam. With a lens,
The pinhole is disposed at a position approximately away from the first collimator lens by a substantially focal length of the first collimator lens,
The camera module includes: a lens; and a first imaging element in which a first light spot is formed by collecting the first parallel light beam by the lens;
The imaging unit is configured to collect a second collimator lens that condenses a second parallel beam obtained by converting the second light reflected by the first imaging element into a substantially parallel shape by the lens. And a second imaging element that generates an image signal obtained by photoelectrically converting the second light spot collected by the second collimator lens,
The control unit includes a calculation unit that calculates a focus evaluation value for the second light spot based on the image signal, and a display unit that displays the second light spot.
The controller determines a distance between the lens and the first image sensor along a direction perpendicular to a light receiving surface of the first image sensor based on the focus evaluation value;
A camera module adjustment apparatus that adjusts the camera module based on the distance.
The camera module includes a lens holding unit that holds the lens,
The camera module adjustment device according to claim 1, further comprising: a lens holding / moving unit that moves the lens holding unit in the direction and moves the lens holding unit to a camera module adjustment position based on the distance.
3. The camera module adjustment device according to claim 1, further comprising a beam splitter that deflects the first parallel light beam to irradiate the camera module, and causes the second parallel light beam to travel straight without being deflected. 4.
The camera module adjustment device according to claim 3, wherein the beam splitter is a half mirror or a non-deflection beam splitter.
The lens is a wide-angle lens or fisheye lens,
5. The camera module adjustment device according to claim 1, wherein the second light is reflected by a reflective diffraction grating on the light receiving surface of the first image sensor. 6.
6. The ultraviolet curable resin is applied to a gap between the lens holding portion and the first image sensor to fix the camera module adjustment position, and the ultraviolet curable resin is irradiated with ultraviolet rays. The camera module adjustment apparatus as described.
A camera module adjustment method including a light source unit, a camera module, a photographing unit, a control unit, and a lens holding and driving unit,
The light source unit converts light emitted from the light source to first light by a pinhole, and converts first light incident from the pinhole to a first parallel light by the first collimator lens,
The pinhole is disposed at a position approximately away from the first collimator lens by a substantially focal length of the first collimator lens,
A first light spot in which the first parallel light beam is condensed on the light receiving surface of the first image sensor of the camera module is formed on the first image sensor by the lens of the camera module.
The imaging unit uses a second collimator lens to convert a second parallel light obtained by converting the second light reflected by the first imaging element into a substantially parallel state by the lens. An image signal obtained by photoelectrically converting the second light spot collected by the second image sensor and the second light spot collected by the second collimator lens by the second image sensor;
The control unit calculates a focus evaluation value for the second light spot based on the image signal by the calculation unit, and displays the second light spot by the display unit,
The controller determines a distance between the lens and the first image sensor along a direction perpendicular to a light receiving surface of the first image sensor based on the focus evaluation value, and based on the distance. And adjusting the camera module.
In the camera module, a lens holding unit holds the lens,
Moving the lens holding part in the direction;
The camera module adjustment method according to claim 7, wherein the lens holding unit driving unit moves the lens holding unit to a camera module adjustment position based on the distance.
The camera module adjustment method according to claim 7, wherein the first parallel light beam is deflected by a beam splitter to irradiate the camera module, and the second parallel light beam goes straight without being deflected.
The camera module adjustment method according to claim 9, wherein the beam splitter is a half mirror or a non-deflection beam splitter.
The lens is a wide-angle lens or fisheye lens,
The camera module adjustment method according to claim 7, wherein the second light is reflected by a reflective diffraction grating on the light receiving surface of the first image sensor.
12. The ultraviolet curable resin is applied to a gap between the lens holding unit and the first image sensor to fix the camera module adjustment position, and the ultraviolet curable resin is irradiated with ultraviolet rays. The camera module adjustment method described.