JP2005031269A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form an image whose brightness is adjusted in accordance with a position. <P>SOLUTION: A liquid crystal light control element 4 equipped with a plurality of ITO films 33-1 to 33-n is disposed on the light receiving surface side of an imaging device 5. In the case of imaging, a light transmittance control part 8 detects the received light quantity of the imaging device 5 for every imaging device 5-1 to 5-n, and applies voltage to guest-host type liquid crystal 13-1 to 13-n respectively based on the result of detection. The directions of the molecules of the liquid crystal 13-1 to 13-n are changed based on the applied voltage. The transmittance of the control element 4 is therefore changed for every light control areas 4-1 to 4-n. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image pickup apparatus that controls the amount of light incident on an image pickup element by a light control element using a liquid crystal such as a guest-host type liquid crystal.
[0002]
[Prior art]
2. Description of the Related Art Image pickup devices including an image pickup device such as a CCD (Charge Coupled Device) are widely used. In this imaging apparatus, the imaging element converts incident light into an electrical signal, converts the electrical signal into a digital signal, and processes the obtained digital signal to generate an image.
[0003]
In the imaging apparatus, the generated image becomes bright when the amount of light incident on the imaging element is large, and the generated image becomes dark when the amount of light incident on the imaging element is small. Therefore, when the amount of light incident on the image sensor is too large or too small, there is a disadvantage that the contour of the generated image becomes unclear or the color becomes unclear.
[0004]
For the reasons described above, the imaging apparatus is provided with a diaphragm that changes the amount of light incident on the imaging element. The diaphragm has a structure in which a plurality of diaphragm blades are overlapped to form a hole at the center. The stop is provided on the light receiving surface side of the image sensor. By providing the diaphragm on the light receiving surface side of the image sensor, the light that has passed through the hole of the diaphragm enters the image sensor.
[0005]
In the diaphragm, the size of the hole changes when the diaphragm blades are driven by the actuator. Accordingly, it is possible to increase the amount of light incident on the image sensor by increasing the hole, and to decrease the amount of light incident on the image sensor by reducing the hole.
[0006]
By the way, in recent years, downsizing of an imaging apparatus has been promoted for reasons such as being convenient for a user to carry. However, when the diaphragm described above is used, it is necessary to provide an actuator for driving the diaphragm blades, and thus it is difficult to reduce the size of the imaging apparatus.
[0007]
On the other hand, there has been proposed an imaging apparatus that controls the amount of light incident on the imaging element using a light control element made of a material having a variable light transmittance such as liquid crystal (see, for example, Patent Document 1). .) In a light control element using liquid crystal (hereinafter referred to as a liquid crystal light control element), a liquid crystal layer is disposed between a pair of transparent substrates, and a transparent electrode layer is provided between the liquid crystal layer and each substrate. It becomes. In the liquid crystal light adjusting device, the voltage applied to the liquid crystal is changed by changing the voltage applied to the electrode layer, and the light transmittance is changed by changing the direction of the liquid crystal molecules. Therefore, the image pickup apparatus can change the amount of light incident on the image pickup element by disposing the liquid crystal light adjusting element on the light receiving surface side of the image pickup element.
[0008]
By adopting the liquid crystal light adjusting element described above instead of the diaphragm using diaphragm blades, the imaging apparatus can be miniaturized because it is not necessary to mount an actuator. Furthermore, it is possible to prevent diffracted light generated by passing through the stop.
[0009]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-326894
[Problems to be solved by the invention]
However, in the liquid crystal dimming element described above, when a voltage is applied to the liquid crystal, a constant voltage is applied to the entire liquid crystal, so that the directions of all the liquid crystal molecules change simultaneously. That is, the light transmittance of the liquid crystal light control device changes at the same rate regardless of the position where the light is transmitted, and the amount of light received by the light receiving surface of the imaging device (the amount of received light) is the same rate regardless of the position. Increase or decrease.
[0011]
Therefore, for example, as shown in FIG. 6, when imaging is performed in a state where there is a high-luminance light source such as the sun in the range A to be imaged, light emitted from the light source is included in the amount of light received by the imaging device. Therefore, the total amount of light received by the image sensor increases. At this time, if the voltage applied to the liquid crystal is controlled based on the total amount of light received by the imaging device, the light transmittance of the liquid crystal light control device is lowered at the same time, so the generated image is dark in the range other than the light source Or problems such as smearing occur. In other words, the generated image has deteriorated quality.
[0012]
The present invention has been proposed in view of the above-described reason, and the amount of light incident on the image sensor is controlled by a dimmer that can change the light transmittance depending on the position where the light is transmitted. Thus, an object of the present invention is to provide an imaging device capable of controlling an image to an appropriate brightness.
[0013]
[Means for Solving the Problems]
An imaging device according to the present invention includes a pair of transparent substrates, a liquid crystal layer formed between the pair of transparent substrates, and a light control element that applies a voltage to the liquid crystal layer for each region. An image sensor that receives the transmitted light of the light control element by a light receiving surface, generates an image signal from the received light, a light receiving amount detecting unit that detects a light receiving amount of the light receiving surface, and a light receiving amount detecting unit. Control means for controlling the light transmittance of the light control element for each region by controlling the voltage applied to the liquid crystal layer by the voltage application unit for each region based on the detected amount of received light. It is characterized by providing.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0015]
As shown in FIG. 1, an imaging apparatus 1 to which the present invention is applied includes a front lens group 2 that transmits light from a subject, a rear lens group 3 that transmits light emitted from a front lens group 2, and a rear lens. A liquid crystal light adjusting element 4 that transmits light emitted from the group 3; an image sensor 5 that receives the light emitted from the liquid crystal light adjusting element 4, converts the light into an image signal, and outputs the image signal; A Y / C signal processing unit 6 that generates a luminance signal Y and a chroma signal C from an image signal, an image sensor driving unit 7 that controls the timing at which the image sensor 5 outputs an image signal, a Y / C signal processing unit 6 and A light transmittance control unit 8 that controls the light transmittance of the liquid crystal light control device 4 based on a signal supplied from the image sensor driving unit 7 is provided.
[0016]
The lens front group 2 includes a plurality of lenses such as a zoom lens group, and the lens rear group 3 includes a plurality of lenses such as an imaging lens.
[0017]
The liquid crystal light adjusting element 4 transmits the light emitted from the rear lens group 3. The light transmittance of the liquid crystal light adjusting device 4 changes based on the control by the light transmittance control unit 8. That is, the liquid crystal light adjusting device 4 can change the amount of light incident on the imaging device 5 by changing the amount of emitted light by changing the light transmittance. Further, as shown in FIG. 2, the liquid crystal light control element 4 is divided into a plurality of regions (hereinafter referred to as light control regions 4-1 to 4 -n), and each light control region 4-1 to 4-4. The light transmittance can be changed every n.
[0018]
Next, the liquid crystal light adjusting device 4 described above will be described in detail. In the following description, the guest host type liquid crystals 13 provided in the light control regions 4-1 to 4-n are referred to as guest host type liquid crystals 13-1 to 13-n, respectively. In addition, regions where the light transmitted through the light control regions 4-1 to 4-n are received by the image sensor 5 are referred to as image sensors 5-1 to 5-n, respectively.
[0019]
As shown in FIG. 3, the liquid crystal light control device 4 includes a guest host type liquid crystal 13 and a spacer 14 disposed between a first stacked body 11 and a second stacked body 12. The liquid crystal 13 and the spacer 14 are sealed with a sealant 15. Hereinafter, the liquid crystal light adjusting element 4 is also referred to as a liquid crystal cell 4.
[0020]
The first stacked body 11 is formed by sequentially stacking a first electrode 22 and a first alignment film 23 on a first glass substrate 21. The second stacked body 12 is formed by sequentially stacking a second electrode 25 and a second alignment film 26 on a second glass substrate 24. The first stacked body 11 and the second stacked body 12 are arranged in a positional relationship in which the first alignment film 23 and the second alignment film 26 face each other.
[0021]
The first electrode 22 and the second electrode 25 include, for example, a transparent conductive film formed by sputtering ITO (Indium Tin Oxide) and then patterning by photolithography.
[0022]
Specifically, as shown in FIG. 4, the first electrode 22 includes an ITO film 31 formed over the entire main surface of the first glass substrate 21. A conductive wire 32 is connected to the ITO film 31.
[0023]
Further, as shown in FIG. 5, the second electrode 25 includes a plurality of ITO films 33-1, 33-2,... 33-n formed in a matrix on the main surface of the second glass substrate 24. Is provided. The ITO films 33-1 to 33-n are formed in the light control regions 4-1 to 4-n, respectively. Further, the ITO films 33-1 to 33-n are connected to conductive wires 34-1 to 34-n, respectively.
[0024]
The first alignment film 23 and the second alignment film 26 set the molecular direction of the guest-host type liquid crystal 13 to a predetermined direction. The first and second alignment films 23 and 26 are formed, for example, by forming a polymer film such as polyimide on the first and second glass substrates 21 and 24 and rubbing the surface.
[0025]
The guest-host type liquid crystal 13 is a mixture of liquid crystal molecules 41 as a host material and dichroic dye molecules 42 as a guest material.
[0026]
The direction of the liquid crystal molecules 41 changes when a voltage is applied. The direction of the dichroic dye molecule 42 changes according to the change in the direction of the liquid crystal molecules 41. The light absorption of the dichroic dye molecule 42 changes depending on the direction. Accordingly, the light transmittance of the liquid crystal light adjusting element 4 is changed by changing the voltage applied to the guest-host type liquid crystal 13. In the present embodiment, the guest-host type liquid crystal 13 uses a light source whose light transmittance increases as the pulse width of the applied voltage increases. However, the light transmittance increases as the pulse width of the applied voltage increases. You may use what goes down.
[0027]
As described above, the liquid crystal light control device 4 includes the plurality of ITO films 33-1 to 33-n formed in the light control regions 4-1 to 4-n. Different voltages can be applied to the guest-host type liquid crystals 13-1 to 13-n every 1 to 4-n (static drive). Therefore, the liquid crystal light control device 4 can change the light transmittance for each of the light control regions 4-1 to 4-n.
[0028]
For example, when the range A shown in FIG. 6 is imaged, the sun enters the imaged range. Therefore, the region where the light emitted from the sun is incident becomes brighter than other regions.
[0029]
By imaging the range A with the imaging device 1, for example, when light emitted from the sun passes through the light control areas 4-1 and 4-2, the transmitted light of the light control areas 4-1 and 4-2 is The light enters the image sensors 5-1 and 5-2. That is, the level of the image signal generated based on the light received by the imaging elements 5-1 and 5-2 is the image signal generated based on the light received by the imaging elements 5-3 to 5-n. Compared to
[0030]
Therefore, by detecting the total amount of light received by the image sensor 5 from the image signal for one screen output from the image sensor 5 and applying the same voltage to the entire guest-host type liquid crystal 13 based on the detected total amount of light received. When the light transmittance of the liquid crystal light control device 4 is controlled all at once, the light transmittance of the liquid crystal light control device 4 is excessively lowered. The level of the image signal is too small, and the obtained image is dark for subjects other than the sun.
[0031]
On the other hand, in the liquid crystal light control element 4, the voltage applied to the guest-host type liquid crystals 13-1 and 13-2 is made smaller than the other regions, thereby transmitting the light control regions 4-1, 4-2. Only the rate can be reduced, and only the level of the image signal output from the image sensors 5-1 and 5-2 can be reduced. Therefore, the obtained image is not dark except for the sun, and the brightness is appropriate throughout.
[0032]
Returning to FIG. 1, the light transmittance controller 8 individually controls the voltages applied to the guest-host type liquid crystals 13-1 to 13-n based on the level of the image signal output from the image sensor 5. As a result, the light transmittance of the liquid crystal light adjusting element 4 is changed for each of the light adjusting regions 4-1 to 4-n. In the present embodiment, the light transmittance control unit 8 drives the liquid crystal light control device 4 by a pulse width modulation (PWM) method.
[0033]
The light transmittance control unit 8 includes a control unit 51 to which signals are supplied from the image sensor driving unit 7 and the Y / C signal processing unit 6, and a pulse generation unit 52 that generates a drive pulse based on control by the control unit 51. And a power source 53 driven by the pulse signal generated by the pulse generator 52.
[0034]
The control unit 51 determines the voltage applied to the guest-host type liquid crystals 13-1 to 13-n based on the luminance signals of the imaging elements 5-1 to 5-n supplied from the Y / C signal processing unit 6. Determine the pulse width. The control unit 51 supplies a signal indicating the determined pulse width to the pulse generation unit 52 in synchronization with the basic clock supplied from the image sensor driving unit 7.
[0035]
The pulse generator 52 generates a drive pulse of the power source 53 as shown in FIG. 7 based on the signal supplied from the control unit 51, and synchronizes with the basic clock supplied from the image sensor driving unit 7. 53.
[0036]
The power supply 53 is driven based on the drive pulse supplied from the pulse generator 52 and applies a voltage to the ITO films 31, 33-1 to 33-n.
[0037]
Next, a method for controlling the amount of light received by the image sensor 5 in the imaging device 1 described above will be described.
[0038]
First, the light transmitted through the lens front group 2 and the lens rear group 3 enters the liquid crystal light control element 4. The liquid crystal light adjusting element 4 emits the incident light and supplies it to the imaging element 5.
[0039]
Next, the image sensor 5 receives the light transmitted through the liquid crystal light control element 4, generates an image signal at a timing synchronized with the basic clock supplied from the image sensor drive unit 7, and generates a Y / C signal processing unit. 6 is supplied.
[0040]
Next, the Y / C signal processing unit 6 generates a luminance signal and a chroma signal from the image signal supplied from the image sensor 5. The luminance signal and the chroma signal are supplied to an image signal processing unit (not shown). Further, the luminance signal is supplied to the control unit 51.
[0041]
Next, the control unit 51 applies a voltage to the guest-host type liquid crystals 13-1 to 13-n based on the luminance signal generated from the image signals output from the image sensors 5-1 to 5-n. Determine the pulse width.
[0042]
A specific method for determining the voltage pulse width by the control unit 51 is as described below. In the following description, a case where the transmittance of the dimming area 4-1 is changed based on the level of the image signal output from the image sensor 5-1 will be described as an example, and will be described using the flowchart shown in FIG. To do.
[0043]
First, in step ST1, the luminance signal of the image sensor 5-1 is supplied from the Y / C signal processing unit 6 to the control unit 51.
[0044]
Next, in step ST2, the control unit 51 determines whether or not the amount of light received by the image sensor 5-1 is a specified value based on the luminance signal supplied in step ST1. When the received light amount is smaller than the specified value, the process proceeds to step ST3. When the received light amount is larger than the specified value, the process proceeds to step ST4. When the received light amount is the specified value, the process returns to step ST1.
[0045]
In step ST3, the control unit 51 sets the width of the drive pulse generated by the pulse generation unit 52 one step wider. That is, a setting is made to increase the transmittance of the light control region 4-1 by one step. Then, the process returns to step ST1.
[0046]
In step ST4, the control unit 51 sets the width of the drive pulse generated by the pulse generation unit 52 to be narrower by one step. That is, a setting is made to lower the transmittance of the light control region 4-1 by one step. Then, the process returns to step ST1.
[0047]
Note that the transmittance of the dimming regions 4-2 to 4-n is similar to the transmittance of the dimming region 4-1 based on the level of the image signal output from the imaging elements 5-2 to 5-n. Be controlled.
[0048]
Next, the pulse generator 52 generates a drive pulse based on the signal supplied from the controller 51 and drives the power supply 53. The power source 53 applies a voltage to each of the guest-host type liquid crystals 13-1 to 13-n, and changes the transmittance of the liquid crystal dimming element 4 for each of the dimming regions 4-1 to 4-n.
[0049]
As described above, in the imaging device 1 to which the present invention is applied, the liquid crystal dimming element 4 in which the second electrode 25 is composed of the plurality of ITO films 33-1 to 33-n is disposed on the light receiving surface side of the imaging element 5. I have. Therefore, in the liquid crystal light control device 4, the voltage applied to the guest-host type liquid crystals 13-1 to 13-n can be changed for each of the light control regions 4-1 to 4-n to change the light transmittance. it can.
[0050]
Further, the light transmittance controller 8 detects the amount of light received by the image sensor 5 for each of the image sensors 5-1 to 5-n, and based on the detected result, the guest-host type liquid crystals 13-1 to 13-n are detected. A voltage is applied. Therefore, according to the imaging apparatus 1 to which the present invention is applied, it is possible to control the amount of light incident on the imaging element 5 for each of the liquid crystal dimming elements 4-1 to 4-n, and the imaging range Even when there is a light source with high brightness, it is possible to generate an image with appropriate brightness throughout.
[0051]
In the image pickup apparatus 1, the liquid crystal light control element 4 is disposed between the rear lens group 3 and the image sensor 5. However, if the liquid crystal light control element 4 is disposed on the light receiving surface side of the image sensor 5. For example, even if it is disposed between the front lens group 2 and the rear lens group 3 as shown in FIG. 9A or on the light incident side of the front lens group 2 as shown in FIG. good.
[0052]
Further, it is most preferable that the liquid crystal light adjusting element 4 is integrated with the image pickup element 5 as shown in FIG. By integrating the liquid crystal light control device 4 and the image sensor 5, the liquid crystal light control device 4 serves as a cover glass that protects the light receiving portion of the image sensor 5, so that it is not necessary to use a cover glass. The cost of the imaging device 1 can be reduced.
[0053]
In addition, in the imaging device 1, the transmittance of the liquid crystal light adjusting element 4 is adjusted for each of the light control regions 4-1 to 4-n in a state where no voltage is applied to the guest-host type liquid crystals 13-1 to 13-n. May be different. When the transmittance of the liquid crystal dimming element 4 is different for each of the dimming regions 4-1 to 4-n, the difference between the luminance signals generated from the image signal generated by imaging the all-white pattern box in advance is calculated. By calculating each dimming area 4-1 to 4-n and recording it in a memory (not shown), it is possible to appropriately control the transmittance of the liquid crystal dimming element 4 by performing correction during imaging. Become.
[0054]
Further, the pattern box is imaged with several settings with different focal lengths from the setting with the shortest focal length (WIDE end) to the setting with the longest focal length (TELE end), and the light control areas 4-1 to 4-4. By calculating the difference of the luminance signal every −n and recording it in a memory (not shown), it becomes possible to perform more accurate correction.
[0055]
In addition, in the imaging device 1, instead of the liquid crystal light adjusting element 4, as shown by arrows R1 and R2 in the drawing, as shown in FIG. 4 may be provided. By providing the liquid crystal light control element 55, the ratio of optical density (absorbance) can be further improved. Further, the imaging device 1 may be provided with a plurality of liquid crystal light control elements 55.
[0056]
In the present embodiment, the shape of the liquid crystal light control element 4 is a rectangle, but the shape of the liquid crystal light control element 4 is not limited to a rectangle, and may be, for example, a circle.
[0057]
The imaging device 1 can change the light transmittance for each pixel by controlling the voltage applied to the guest-host type liquid crystal 13 instead of the liquid crystal light adjusting element 4 for each pixel. A liquid crystal light control element may be provided.
[0058]
As the liquid crystal light control device capable of changing the light transmittance for each pixel, the liquid crystal light control device 61 capable of dynamic driving shown in FIG. 12 and the liquid crystal light control device capable of active matrix driving shown in FIG. 62. In the following description, the number of pixels of the image sensor 5 is assumed to be a × b = c pixels. A direction in which a pixels are formed is referred to as an x direction, and a direction in which b pixels are formed is referred to as a y direction.
[0059]
As shown in FIG. 12A, the liquid crystal light control element 61 capable of dynamic driving corresponds to each pixel of the image sensor 5 (hereinafter referred to as an a × b area (hereinafter referred to as light control areas 71-1 to 71-). c)). As shown in FIG. 12B, the liquid crystal light adjusting device 61 includes first ITO films 72-1 to 72-b formed so as to cover a light adjusting regions arranged in a line along the x direction. The ITO film 74- is provided so as to cover the dimming regions arranged in b along the y direction as shown in FIG. 12C. The liquid crystal light control device 4 has the same configuration except that the second electrode 75 including 1 to 74-a is provided instead of the second electrode 24. The ITO films 72-1 to 72-b and the ITO films 74-1 to 74-a are formed so that their intersections correspond to the light control regions 71-1 to 71-c.
[0060]
In the liquid crystal light adjusting device 61, the voltage applied to the ITO films 72-1 to 72-b and the voltage applied to the ITO films 74-1 to 74-a are controlled to control each light adjusting region 71-1. It becomes possible to change the light transmittance of ˜71-c. That is, the light transmittance can be changed for each pixel. The imaging apparatus 1 can control the amount of light received by the imaging element 5 for each pixel by providing the liquid crystal light adjusting element 61.
[0061]
In addition, as shown in FIG. 13A, the liquid crystal light control device 62 capable of active matrix driving corresponds to the pixels of the image sensor 5 and corresponds to an a × b region (hereinafter, light control regions 81-1 to 81-1). 81-c.). Then, as shown in FIG. 13B, the second electrode 25 including the ITO films 82-1 to 82-c formed in the light control regions 81-1 to 81-c is replaced with the second electrode 25. The liquid crystal light control element 4 has the same configuration except that it is provided in place of the above. Each ITO film 82-1 to 82-c is connected to a signal line (not shown) via a switch (not shown), and a voltage is applied via the signal line when the switch is turned on.
[0062]
The liquid crystal light control device 62 capable of active matrix driving has a faster change in the direction of liquid crystal molecules relative to the applied voltage than the liquid crystal light control device 61 capable of dynamic driving. Therefore, the imaging apparatus 1 includes the liquid crystal light control element 62 capable of active matrix driving, so that the amount of light received by the imaging element 5 can be controlled for each pixel, and the transmittance with respect to the applied voltage. Changes quickly.
[0063]
【The invention's effect】
Further, in the imaging device according to the present invention, a light control element including a voltage applying unit that applies a voltage to the liquid crystal layer for each region is provided on the light receiving surface side of the image sensor. The transmitted light enters the image sensor. That is, the light control element can change the light transmittance by changing the voltage applied for every area | region. The detection means detects the amount of light received by the image sensor for each area, and controls the voltage applied to each area of the liquid crystal layer by controlling the voltage application means based on the amount of light received by the control means. .
[0064]
Therefore, according to the imaging apparatus according to the present invention, it is possible to control the amount of light incident on the imaging element for each region, and even when there is a variation in brightness in the imaging range, It becomes possible to generate an image with brightness.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an imaging apparatus to which the present invention is applied.
FIG. 2 is a diagram illustrating n light control regions provided in a liquid crystal light control element provided in the imaging apparatus.
FIG. 3 is a cross-sectional view showing a liquid crystal light adjusting device provided in the imaging apparatus.
FIG. 4 is a schematic diagram illustrating a first electrode provided in a liquid crystal light adjusting device provided in the imaging apparatus.
FIG. 5 is a schematic diagram illustrating a second electrode provided in a liquid crystal light adjusting device provided in the imaging apparatus.
FIG. 6 is a diagram illustrating a range imaged by an imaging device.
FIG. 7 is a flowchart for explaining the operation of a control unit provided in an imaging apparatus to which the present invention is applied.
FIG. 8 is a diagram showing drive pulses generated by a pulse generator provided in an imaging apparatus to which the present invention is applied.
FIG. 9 is a diagram for explaining a position including a liquid crystal light adjusting device.
FIG. 10 is a diagram in which a liquid crystal light control device and an imaging device are integrated.
FIG. 11 is a diagram showing a liquid crystal light control device in which two liquid crystal cells are integrated so that the directions of optical axes are orthogonal to each other.
FIG. 12 is a diagram showing a liquid crystal light control element that is dynamically driven.
FIG. 13 is a diagram illustrating a liquid crystal light control element that is driven in an active matrix.
[Explanation of symbols]
4 liquid crystal light control device, 5 imaging device, 13 guest host type liquid crystal, 31 ITO film, 33-1 to 33-n ITO film,

Claims (5)

A light control element having a pair of transparent substrates, a liquid crystal layer formed between the pair of transparent substrates, and a voltage applying unit that applies a voltage to the liquid crystal layer for each region;
An image sensor that receives the transmitted light of the light control element by a light receiving surface and generates an image signal from the received light;
A received light amount detecting means for detecting the received light amount of the light receiving surface;
Based on the received light amount detected by the received light amount detecting means, the voltage application means controls the voltage applied to the liquid crystal layer for each area, thereby controlling the light transmittance of the dimmer element in the area. An image pickup apparatus comprising: a control unit that controls each time. The imaging apparatus according to claim 1, wherein the liquid crystal layer is formed of a guest-host type liquid crystal. 3. The imaging apparatus according to claim 2, wherein the guest-host type liquid crystal has a host material of liquid crystal molecules and a guest material of dichroic dye molecules. The imaging apparatus according to claim 1, wherein the light control element and the imaging element are integrated. The voltage application means provided in the light control element applies a voltage to the liquid crystal layer for each pixel,
The received light amount detecting means detects the received light amount of the light receiving surface for each pixel,
The control means controls the light transmittance of the light control element for each pixel by controlling the voltage applied to the liquid crystal layer by the voltage application means for each pixel. The imaging device described.

Images