JP2000032354A - Image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image pickup device capable of being added with a high-grade image pickup function and being made thin in thickness. SOLUTION: Light L1 from an object is made incident to a light shielding plate 3 and passed through respective plural apertures 3a and afterwards, images are formed on plural area sensors 11 by plural microlenses 2a. In this case, the subject formed on each area sensor 11 is the entire image of the object. Therefore, the plural entire images of the object are picked up by the plural area sensors 11. Besides, plural optical systems composed of sections corresponding to optical paths from the apertures 3a of the light shielding plate 3 through the microlenses 2a to the area sensors 11 provided at a recessed part 1a are respectively independent and provide peculiar optical characteristics for each area sensor 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image pickup apparatus for picking up an image.

[0002]

2. Description of the Related Art Some imaging devices such as video cameras use a solid-state imaging device such as a CCD (Charge Coupled Device). In an imaging device using this solid-state imaging device,
Generally, an image is formed by forming a subject image on a solid-state imaging device by a lens unit constituting a single optical system. The structure of such a device can be said to be close to a "monocular" which is the structure of a vertebrate eye such as a human.

With respect to the imaging device having a single-eye structure, an imaging device using a “compound eye” which is an insect eye structure has recently been proposed. The imaging device using a compound eye has an advantage that the optical system can be made smaller in size as compared with the imaging device using a single eye, so that the device can be made thinner. As an example of the device using the compound eye, there is, for example, a device named “panel-type image sensor” described in “Electronics 1993. May, p62-p65”. This panel-type image sensor includes a photodiode array in which a plurality of photodiodes are arranged, a lens array in which a plurality of small lenses are arranged at positions corresponding to the plurality of photodiodes, and a photodiode array. A pinhole array in which a plurality of pinholes each serving as a stop for each of a plurality of small lenses are arranged between the lens array and the plurality of small lenses has a layered structure. In this panel type image sensor,
Partial light from the subject is incident on individual photodiodes by individual small lenses in the lens array. From the photodiode, a signal corresponding to the incident light is output. In this panel-type image sensor, signals output from individual photodiodes forming a compound eye correspond to partial images of a subject, and signals output from a plurality of photodiodes are combined to form an entire image of the subject. Is obtained.

Several other techniques using such a compound eye structure have been disclosed. For example, Japanese Patent Application Laid-Open No. 1-280978 relates to an image pickup display device having a compound eye image pickup function. The technology is described. Further, Japanese Patent Application Laid-Open No. H8-10924 describes a technique relating to an image input / output device having an image pickup function with a compound eye.

[0005]

By the way, in the above-described monocular imaging apparatus, in order to adjust the focus of the optical system or to realize the zoom function, the position of a lens constituting the optical system is moved. A method of changing the angle of view of the optical system or the like is generally used. However, in order to move the lens, a mechanical lens moving mechanism is required, so that the configuration of the lens unit becomes large, which hinders a reduction in the thickness of the apparatus. .

In a compound eye imaging device, although the thickness of the device can be reduced, since the lens is integrated with the device, the optical characteristics such as the angle of view and the focal length are structurally different depending on the subject. It is difficult to make the variable, and advanced imaging functions such as an optical focus adjustment and a zoom function have not been added. For this reason, there is a problem that only a simple imaging function can be realized as compared with a monocular imaging device. Further, for example, in the above-mentioned “panel-type image sensor”, since one lens is provided corresponding to one photodiode, the effective diameter of the lens is too small, whereby the amount of light incident on the photodiode is reduced. Is limited, and the obtained image becomes dark.

[0007] The present invention has been made in view of the above problems, and an object of the present invention is to provide an imaging apparatus capable of adding an advanced imaging function and reducing the thickness of the apparatus. It is in.

[0008]

An image pickup apparatus according to the present invention includes a plurality of image pickup devices each of which is independently electrically driven and each of which independently outputs a signal corresponding to light from a subject. And a plurality of optical systems provided at positions corresponding to each of the plurality of image sensors, each of which makes light from a subject incident on the plurality of image sensors with unique optical characteristics. .

In the imaging apparatus according to the present invention, a signal corresponding to light from a subject is independently output by each of the plurality of imaging elements which are electrically independently driven. Further, light from a subject is incident on the plurality of imaging elements with unique optical characteristics by each of the plurality of optical systems provided at positions corresponding to the plurality of imaging elements.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

[First Embodiment] First, the first embodiment of the present invention will be described.
An embodiment will be described.

FIG. 1 is a sectional view showing an example of a configuration of an image pickup apparatus according to a first embodiment of the present invention. FIG.
FIG. 3 is a plan view of the support substrate 1 shown in FIG. 1, and FIG.
FIG. 2 is a plan view of the microlens array 2 shown in FIG.
The cross sections of the support substrate 1 and the microlens array 2 in the imaging device shown in FIG. 1 correspond to the cross sections taken along line AA ′ in FIGS. 2 and 3, respectively. As shown in FIG. 1, an imaging device 10 according to the present embodiment includes a support substrate 1, a microlens array 2 stacked on the surface of the support substrate 1, and a microlens array 2 attached to the surface of the microlens array 2. And a light shielding plate 3.

On the surface of the supporting substrate 1, a plurality of recesses 1a are provided.
Are two-dimensionally arranged in the vertical direction (h direction in FIG. 2) and the horizontal direction (w direction in FIG. 2).
In addition, CC is provided at the center of each of the plurality of recesses 1a.
An area sensor 11 composed of an image sensor such as D is arranged. By arranging the area sensors 11 in the plurality of recesses 1a of the support substrate 1 in this manner, for example, light incident on one area sensor 11 is prevented from being incident on an adjacent area sensor 11. It has become so.

The micro lens array 2 is made of an optically transparent member, and has a plurality of area sensors 1 on its surface.
A plurality of microlenses 2a are formed so as to face each other at positions corresponding to the respective ones, so that their central axes pass through the central position of the area sensor 11. The micro lens 2a is formed by a spherical surface or an aspherical surface.

The light shielding plate 3 has a plurality of micro lenses 2a.
A plurality of openings 3a are formed at positions corresponding to the above. In the light-shielding plate 3, light incident on positions other than the plurality of openings 3a is blocked so as not to enter the device. The plurality of openings 3a correspond to optical stops of the microlenses 2a. In the light shielding plate 3, at least one of the plurality of openings 3a is selectively provided with an infrared cut filter 3b for removing infrared light that is unnecessary for normal imaging. The infrared cut filter 3b is provided in consideration of the fact that the area sensor 11 such as a CCD has sensitivity to infrared light. By selectively attaching the infrared cut filter 3b, a good image signal can be generated based on the light from which the infrared light has been removed by the infrared cut filter 3b during normal imaging. Further, by generating an image signal based on light passing through the opening 3a to which the infrared cut filter 3b is not attached, for example, infrared imaging suitable for darkness can be performed. In addition, for example, if the apparatus is used only for normal imaging, the infrared cut filter 3b may be provided in all the openings 3a. Since there is a possibility that the amount of attenuation may increase, it is desirable to partially provide the attenuation. Further, the infrared cut filter 3b can be omitted from the configuration of the device.

In this embodiment, the light L1 from the subject
Is incident on the light shielding plate 3, passes through each of the plurality of openings 3a, and is imaged on the plurality of area sensors 11 by each of the plurality of microlenses 2a. here,
The subject image formed on each area sensor 11 is the entire image of the subject. Therefore, in the present embodiment, a plurality of whole images of the subject are captured by the plurality of area sensors 11. In the present embodiment, a portion corresponding to an optical path from the opening 3a of the light shielding plate 3 through the microlens 2a to the area sensor 11 provided in the concave portion 1a corresponds to the optical system in the present invention. is there. In the present embodiment, a plurality of optical systems are formed corresponding to the area sensor 11. These plurality of optical systems are independent from each other, and each provide a unique optical characteristic to the area sensor 11.

FIG. 4 is an explanatory diagram for describing the optical characteristics of the optical system according to the present embodiment. In the present embodiment, the focal length, which is one of the optical characteristics, differs depending on the location of the plurality of microlenses 2a in the installation location, for example, in the w direction in FIG. For example, a plurality of micro lenses 2a, in w-direction in FIG. 3, a micro lens 2a ₁ of focal length f _1, a microlens 2a ₂ of the focal length f _2, a microlens 2a ₃ a focal length f _3, a focal distance microlens 2a ₄ of f ₄ are arranged in order. At the positions corresponding to these micro lenses 2a ₁ , 2a ₂ , 2a ₃ , 2a ₄ , the area sensors 11 ₁ , 11 ₂ , 11 ₃ ,
11 ₄ are disposed. Here, in the example of FIG. 4, the focal lengths of the plurality of microlenses 2a are made different by changing the curvature of the surface. The value of the focal length f ₁ is
For example, it is 0.5 m, and the value of the focal length f ₂ is, for example, 1
m. The value of the focal length f ₃ is, for example, 2 m, and the value of the focal length f ₄ is, for example, 10 m.

The focal lengths of the plurality of microlenses 2a are not limited to the w direction but may be different in the h direction in FIG. Further, the focal lengths may be made different in both the w direction and the h direction. Furthermore, the focal lengths to be varied are not limited to four,
The focal lengths may differ by more or less than four. Further, the value of each focal length is not limited to the above value.

FIG. 5 is an explanatory diagram showing an example of the configuration of the area sensor 11. The area sensor 11 is, for example, a so-called interline transfer (I
It is composed of a T) type CCD. in this case,
The area sensor 11 includes a plurality of light receiving units 12 arranged in a matrix, a plurality of vertical shift registers 13 connected to the light receiving units 12 for one column via the readout gate 16, respectively, A horizontal shift register 14 is connected to a lower end of the horizontal shift register 13, and an output unit 15 is connected to one end of the horizontal shift register 14.

Although not shown, in the area sensor 11, for example, an overflow barrier composed of a P ^- layer is formed on an N-type semiconductor substrate, and an electric charge composed of an N ⁺ layer constituting the light receiving section 12 is formed on the overflow barrier. An accumulation unit and a transfer channel composed of an N ⁺ layer constituting the vertical shift register 13 are formed. A read gate 16 is formed between the charge storage section and the transfer channel. A channel stop composed of a P ⁺ layer is formed between adjacent pixels. Furthermore, P ⁺
A virtual gate composed of layers is formed. In the area sensor 11, the signal charge stored in the charge storage section is swept away by the substrate based on an electronic shutter signal SUB output from a timing generation circuit 31 described later, thereby realizing an electronic shutter function. ing.

FIG. 6 shows an image pickup apparatus 10 according to this embodiment.
FIG. 3 is a block diagram showing a circuit configuration of FIG. The imaging device 10
A vertical synchronizing signal VD and a horizontal synchronizing signal H output from a synchronizing signal generator (not shown)
D, a timing generation circuit 31 that creates and supplies various driving pulse signals to each of the plurality of area sensors 11, and an output signal from the area sensor 11 that is provided corresponding to the plurality of area sensors 11. And a plurality of analog signal processing units 32 for performing predetermined analog signal processing on the analog output signals from the plurality of analog signal processing units 32.
A / D. A) a plurality of A / D conversion circuits 33 for performing conversion and outputting digital signals; and performing predetermined digital signal processing on digital output signals from the plurality of A / D conversion circuits 33 to generate image data. A digital signal processing unit 34, an image memory 35 for temporarily storing image data output from the digital signal processing unit 34, and each component of an apparatus including the timing generation circuit 31, the digital signal processing unit 34, and the image memory 35 And a digital-to-analog (hereinafter, referred to as D / A) conversion of the digital image signal from the digital signal processing unit 34 to convert the analog signal to a monitor device for image display. becomes image and the D / a conversion circuit 37 for outputting data V _out1, the digital image signal to a computer and various SL from the digital signal processing unit 34 And a interface 38 for output as image data V _out2 of the medium.

The control unit 36 includes a digital signal processing unit 34
An external instruction signal S1 relating to the setting of various image processings performed in step ( ₁₎ is input. The control unit 36 includes, for example, a CPU (Central Processing Unit). The interface 38 is, for example, an RS-
232C and SCSI (Small Computer System Interface)
e) meet the connection standards.

The driving pulse signal supplied from the timing generation circuit 31 to the area sensor 11 includes, for example,
A drive pulse V for the vertical shift register which is a timing signal for charge transfer of the vertical shift register 13, a drive pulse H for a horizontal shift register which is a timing signal for charge transfer of the horizontal shift register 14, and an instruction to sweep out signal charges in the electronic shutter function. Electronic shutter signal S for
UB, a clock pulse CK, and the like. Note that the driver 31a outputs, for example,
The vertical shift register drive pulse V and the electronic shutter signal SUB are supplied.

Although not shown, the analog signal processing section 32 includes, for example, an S / H circuit for performing a sample hold (hereinafter, referred to as S / H) on an output signal from the area sensor 11 and an S / H circuit for performing the S / H operation. It has a CDS circuit or the like that performs CDS (correlation double sampling) processing on the output signal after waveform shaping by the H circuit to remove random noise included in the output signal.

The digital signal processor 34 performs various kinds of signal processing on a plurality of output signals output from the plurality of area sensors 11, and outputs at least one predetermined unit of image signal, for example, an image of a single frame. A signal is generated and output.

Next, with reference to FIGS. 7 to 11, various processes for realizing an advanced imaging function in the imaging apparatus 10 according to the present embodiment will be described together with the operation of the imaging apparatus 10. FIG.

First, a process for improving the resolution in the imaging device 10 will be described. Here, FIG.
As shown in, by the imaging device 10 according to the present embodiment, for example, consider the case of imaging a two subjects O1, O2 with the imaging device 10 at a distance f _3. In FIG. 7, the axis C0 is the central axis of the imaging device 10, and the line indicated by reference numeral w1 is an axis passing through the central axis C0 in the w direction. The subjects O1 and O2 are located at equal intervals in the w direction with respect to the central axis C0.

FIG. 8 shows an example of the imaging conditions shown in FIG.
3 shows output characteristics of signals output from a plurality of area sensors 11. In this figure, the vertical axis indicates the output level of the signal from the area sensor 11, and the horizontal axis indicates the position of each pixel constituting the area sensor 11 in the w direction. Also, in this figure, (A) shows the output characteristics from the area sensor 11 on the assumption that the microlens 2a has ideal optical characteristics.
(B) to (E) show the output characteristics of the signal output from the area sensor 11 incorporated in the actual imaging device 10. That is, (B) shows the focal length f ₄
Shows the output characteristic of the micro-lens 2a ₄ area sensor 11 provided at positions corresponding to the _4. Also,
(C) shows the output characteristic of the focal length f ₃ of the micro lenses 2a ₃ area sensor 11 provided at positions corresponding to the _3. (D) is a focal length f ₂ of the micro lenses 2a ₂ area sensor 11 provided at positions corresponding to the ₂
Shows the output characteristics. (E) shows the output characteristic of the area sensor 11 ₁ provided at a position corresponding to the micro lenses 2a ₁ of focal length f _1. Here, the area sensor 11 ₁ to 11 _4, for example, the axis w in FIG. 7
1 is provided at a position corresponding to 1.

As can be seen from FIG.
Output characteristics of the area sensor 1 which can obtain the optical characteristics of the just-focus with respect to the subjects O1 and O2.
1 has a ₃ is output characteristic Figure 8 (C) if the highest resolution (resolution), then if shown in FIG. 8 (B) has a high resolution. By the way, in the present embodiment, the micro lens 2a has a single lens configuration. However, in the single lens configuration, correction of the field curvature cannot be performed completely in principle. Even in case C),
An ideal output characteristic as shown in FIG. 8A cannot be obtained. Therefore, in the present embodiment, the digital signal processing unit 34 performs predetermined signal processing to improve the resolution.

FIG. 9 is an explanatory diagram for explaining signal processing performed by the digital signal processing section 34 on an output signal having the characteristics shown in FIG. 8, for example. First, the digital signal processing unit 34 has the highest resolution shown in FIG.
8 having the second highest resolution from the output signal of FIG.
A process of subtracting the output signal of (B) is performed. Note that the object of the subtraction processing on the output signal having the highest resolution here is not limited to the output signal of FIG.
The output signal of (D) may be used. However, in order to improve the resolving power, it is desirable that the output signal having the second highest resolution is subjected to the subtraction processing. Here, FIG.
FIG. 4 is a diagram showing characteristics of an output signal after such subtraction processing. Subsequently, the digital signal processing unit 34 is configured as shown in FIG.
The processing of adding the output signal of FIG. 8C to the output signal of FIG. FIG. 9B is a diagram illustrating characteristics of the output signal after such addition processing. By performing the above signal processing, a signal having a higher resolution than the original output signal (FIG. 8C) can be obtained.

The determination of the resolution of the output signals from the plurality of area sensors 11 is performed with respect to the digital signal processing unit 3.
In step 4, for example, the absolute value of the value obtained by performing a differential operation on the output signal of FIG. 8 is obtained, and further integrated to obtain an integrated value corresponding to the contrast. It can be determined to be high. Note that this determination may be performed by the digital signal processing unit 34, but the digital signal processing unit 34 may perform only arithmetic processing, and the determination may be performed by the control unit 36.

Next, referring to FIG.
A process for expanding the dynamic range of the output signal will be described. In FIG. 10, the vertical axis indicates the level of the output signal from the area sensor 11, and the horizontal axis indicates
The illuminance by the light from the subject in the area sensor 11 is shown. In addition, in the drawing, the ranges indicated by reference numerals D ₁ and D ₂ correspond to the magnitude of the dynamic range. In the present embodiment, in each of the plurality of area sensors 11, the exposure time by the electronic shutter can be independently changed, and this is used to expand the dynamic range.

In FIG. 10, reference numeral 52 indicates output characteristics when exposure is performed for a normal time (for example, 1/60 second). If the normal exposure is performed, for example, the illuminance is at the E2, the output value of the area sensor 11 is saturated at V _1. In this case, the magnitude of the dynamic range becomes D _1. In FIG. 10, reference numeral 53 denotes a short time (for example, 1/60) by the electronic shutter.
4 shows output characteristics when exposure is performed for a time shorter than one second. Short time when the exposure is performed, for example, the illuminance is at the E3 (E3> E2), the output value of the area sensor 11 is saturated at V _1. In the case of the short-time exposure, although the illuminance before saturation is more than that in the case of the normal exposure, in particular, S
/ N ratio decreases. Reference numeral 51 indicates an output characteristic obtained when integrating output signals from a plurality of area sensors 11 that have been exposed for a normal time and combining the output signals. In this case, for example, the illuminance is at the E1 (E1 <E2), the output value of the area sensor 11 is saturated at V _1. Also, in this case, although there is no margin in the illuminance until saturation compared to the case of the output characteristic 52 of the area sensor 11 which has been exposed for the normal time, the S / N ratio in the low illuminance region is particularly large. Becomes larger.

In the present embodiment, the output characteristics of the area sensor 11 due to the difference in exposure time as described above are taken into consideration, and the digital signal processing unit 34 uses the area sensor 11 to generate an image signal in accordance with the illuminance. The output signal is selectively switched. For example, if the illuminance is E1
In the range up to, a signal obtained by integrating output signals from the plurality of area sensors 11 that have been exposed for a normal time and combining them is used for generating an image signal in the digital signal processing unit 34. At this time, the output signal combining process is performed by the digital signal processing unit 34. When the illuminance is in the range from E1 to E2, a single area sensor 1 that has been exposed for a normal time is used.
1 is used to generate an image signal. Further, when the illuminance is in the range from E2 to E3, an output signal from the area sensor 11 that has been exposed for a short time by the electronic shutter is used for generating an image signal. By switching the output signal used to generate the image signal in accordance with the illuminance, the dynamic range size is changed from the normal value D ₁ to D _2.
For example, it is possible to perform imaging without causing overexposure or the like for a bright subject, and perform imaging with high sensitivity and a good S / N ratio for a dark subject. The switching operation of the output signal is performed by the digital signal processing unit 34 or the control unit 36.

Next, a process for realizing high-speed shooting will be described with reference to FIG. In the present embodiment, the plurality of area sensors 11 can be driven at different timings, and can output signals corresponding to light from the subject at different timings. In the present embodiment, high-speed imaging is realized by utilizing this function and the function of short-time exposure by an electronic shutter. In FIG. 11, (A)-
(F) shows a drive timing chart for each of the different area sensors 11. In this timing chart, a period t ₁ indicates a charge accumulation period in the case where short exposure using the electronic shutter is performed in the area sensor 11. In the present embodiment, one cycle of the charge accumulation period is, for example, one field (1/60 second). The period t ₂ is
Shows a period of outputting the electric charge accumulated in the period t _1.

In this embodiment, when high-speed photography is performed, short-time exposure using an electronic shutter is performed in each of the plurality of area sensors 11 at timing slightly shifted. At this time, signals are output from each of the plurality of area sensors 11 at time intervals slightly shifted in accordance with the timing at which the exposure is performed. In this way, by performing the exposure at timing slightly shifted by each of the plurality of area sensors 11, it is possible to perform imaging at a higher speed than the signal output speed by only the single area sensor 11. The output signal from the area sensor 11 obtained by slightly shifting the timing in this manner is temporarily stored as image data in the image memory 35 via the digital signal processing unit 34. The image data temporarily stored in the image memory 35 passes through the digital signal
It is output at a time interval larger than the shift amount of the drive timing of No. 1. As described above, by delaying the output time interval of the image data finally output from the digital signal processing unit 34 with respect to the output time interval of the image signal output from each area sensor 11, high-speed shooting is achieved. Slow reproduction of an image becomes possible.

As described above, according to the imaging apparatus 10 of the present embodiment, each is driven electrically independently, and each independently outputs a signal corresponding to light from a subject. And a plurality of optics provided at positions corresponding to each of the plurality of area sensors 11 and each of which causes light from a subject to enter the plurality of area sensors 11 with unique optical characteristics. And performs appropriate signal processing on output signals obtained from the plurality of area sensors 11 in accordance with a shooting situation. Therefore, as in a conventional imaging apparatus, a lens is moved to focus. There is no need to make adjustments, mechanical focus adjustment mechanism can be omitted from the configuration,
The thickness of the device can be reduced. Thereby, for example, a card-shaped thin imaging device can be manufactured. Further, since the digital signal processing unit 34 performs appropriate signal processing according to the shooting situation, it is possible to obtain an image signal having a high sensitivity and a high dynamic range, and an advanced imaging function such as a high-speed shooting. Can be realized.

As described above, according to the imaging apparatus 10 of the present embodiment, it is possible to add an advanced imaging function and to reduce the thickness of the apparatus.

[Second Embodiment] Next, a second embodiment of the present invention will be described.
An embodiment will be described. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

FIG. 12 is an explanatory diagram showing an example of the configuration of an imaging device according to the second embodiment of the present invention. In the first embodiment, the microlenses 2a
Is made different depending on the installation location, but in the present embodiment, the distance Z1 between the microlens 2a and the area sensor 11 is made different depending on the location, so that each of the plurality of area sensors 11 Are different from each other. The distance Z1 between the microlens 2a and the area sensor 11 can be made different, for example, by changing the depth of the concave portion 1a of the support substrate 1 on which the area sensor 11 is arranged depending on the location. The distance Z1 can be made different by changing the height of the formation position of the microlenses 2a in the microlens array 2 depending on the location.

In the present embodiment, for example, the plurality of microlenses 2a have different imaging angles of view of the area sensors 11 in the h direction (see FIG. 3). For example, in the present embodiment, in the h direction, the area sensor 11 ₁₁ imaging angle theta _1, the area sensor 11 of the imaging angle theta _{2 12}
, An area sensor 11 ₁₃ having an imaging angle of view θ ₃ , and an imaging angle of view θ
An area sensor 11 _{14 4} are arranged in order. At the positions corresponding to the area sensors 11 ₁₁ , 11 ₁₂ , 11 ₁₃ , 11 ₁₄ , the micro lenses 2a ₁₁ , 2a ₁₂ , 2
a ₁₃ and 2a ₁₄ are arranged. The height of the forming position of the microlens 2a in the microlens array 2, microlenses 2a ₁₁ is the lowest, the micro lenses 2a ₁₄
Is the highest. The depth of the recess 1a of the supporting substrate 1 is most shallow portion area sensor 11 ₁₁ is disposed, the portion area sensor 11 ₁₄ are arranged is deepest. Thus, the distance Z1 between the micro lenses 2a and the area sensor 11, the smallest distance between the micro lens 2a ₁₁ and the area sensor 11 _11, the distance between the micro lens 2a ₁₄ and the area sensor 11 ₁₄ Is the largest. Thus the imaging angle of view, imaging angle theta ₁ is largest, imaging angle theta ₄ is the smallest.

The angle of view of the plurality of microlenses 2a is not limited to the h direction but may be different in the w direction in FIG. Further, the imaging angle of view may be made different in both the w direction and the h direction. Furthermore, the imaging angle of view to be varied is not limited to four,
The imaging angle of view may be different by more or less than four.

In this embodiment, the area sensors 11 ₁₁ ,
From 11 ₁₂ , 11 ₁₃ , and 11 ₁₄ , signals corresponding to the respective angle of view are output. The digital signal processing unit 34 controls the area sensors 11 ₁₁ , 11 ₁₂ , 1 according to the shooting conditions.
1 _13, 11 of the output signal from _14, to generate a selectively acquired by the image signal from any one of the output signal. As described above, by appropriately switching and using the output signal corresponding to the imaging angle of view according to the shooting situation, the same as the zoom lens in the conventional monocular imaging apparatus without using a mechanical lens moving mechanism. A zoom function can be realized. Each micro lens 2a ₁₁ , 2a ₁₂ , 2
If the focal length of a _13, 2a ₁₄ are the same, corresponds to the telephoto side of the largest area sensor 11 ₁₁ zoom imaging angle, wide-angle side of the smallest area sensor 11 ₁₄ imaging angle zoom Is equivalent to

In this embodiment, only the imaging angle of view is changed as the optical characteristic. However, the imaging angle of view is changed and the micro lens 2 is changed in the same manner as in the first embodiment.
The focal length a may be changed according to the installation location. By changing the imaging angle of view and the focal length as optical characteristics, focus adjustment in the zoom function can be performed without mechanical movement of the lens. As a result, a zoom function without image quality degradation can be realized.

As described above, according to the imaging apparatus of the present embodiment, the area sensors 11 having different imaging angles of view are provided.
Since the image signal is generated by selectively acquiring the output signal from the camera, the zoom function can be realized without using a mechanical lens moving mechanism.

Other configurations, operations, and effects of the present embodiment are the same as those of the first embodiment.

[Third Embodiment] Next, a third embodiment of the present invention will be described.
An embodiment will be described. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

FIGS. 13 and 14 are explanatory diagrams for explaining an image pickup apparatus according to the third embodiment of the present invention. In the present embodiment, an image quality improvement technique by so-called “pixel shift” is used, in which the number of effective pixels is increased by synthesizing a plurality of images captured with slightly shifted pixel positions, thereby improving the image quality.

The imaging apparatus according to the first embodiment is configured so that the center axis of all the microlenses 2a and the normal line at the center position of each area sensor 11 coincide with each other. the form image pickup apparatus, as shown in FIG. 13, the microlenses 2a ₂₁ to the center position of the center axis C1 and the area sensor 11 ₂₁ as in the first embodiment the lens is arranged to coincide which has a is configured to have a micro-lens 2a ₂₂ disposed so as to shift the normal C2 'at the center position of the center axis C2 and the area sensor 11 ₂₂ of the lens. Central axis C2 of the micro lenses 2a ₂₂ is subject image formed on the area sensor 11 _22, the subject image formed on the area sensor 11 _21, for example, the law to be shifted by 1/2 pixels It is offset with respect to line C2 '.

FIG. 14 shows the area sensors 11 ₂₁ , 1 formed by the micro lenses 2 a ₂₁ , 2 a ₂₂ arranged as described above.
Is a diagram showing the difference of the object image 61 are imaged 1 _22. In this figure, (A) shows the area sensor 11 ₂₁
(B) shows the area sensor 1
Imaging plane of the 1 ₂₂ is shown. Subject image formed on the area sensor 11 _22, to the object image formed on the area sensor 11 _21, for example, as shifted by 1/2 pixels. The area sensors 11 ₂₁ and 11 ₂₂ output signals corresponding to the subject image formed by being shifted from each other by 画素 pixel. Digital signal processing unit 34
Synthesizes two signals from the area sensors 11 ₂₁ and 11 ₂₂ to generate one image data. Thus, 1 /
By synthesizing two signals corresponding to the subject image formed by being shifted by two pixels, the resolution is doubled.

As described above, according to the imaging apparatus of the present embodiment, the resolution can be increased by synthesizing a plurality of signals obtained by slightly shifting the positions of the pixels.

Other configurations, operations, and effects of the present embodiment are the same as those of the first embodiment.

[Fourth Embodiment] Next, a fourth embodiment of the present invention will be described.
An embodiment will be described. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

The imaging apparatus according to the present embodiment uses a holographic stereogram (hereinafter, referred to as holographic stereogram) using holography.
Called HS. ) Is used for generating image data.

First, the outline of the HS will be described with reference to FIG. In the following, only the horizontal parallax (Ho
rizontal Parallax Only: Hereinafter also referred to as HPO. ) Will be described. The HPO one-step HS is composed of a large number of slit-shaped holograms (element holograms). On each element hologram, an image displayed on a display means such as a liquid crystal light valve is projected in a non-parallax direction (vertical direction).
Light is collected and recorded in the parallax direction (left-right direction). Such element hologram exposure is performed on the entire hologram. As a result, the image recorded on each element hologram is a two-dimensional image, but the image exposed on each element hologram has appropriate parallax information, so that the entire image has horizontal parallax. A three-dimensional image can be obtained.

Here, the image to be displayed on the display means such as a liquid crystal light valve is generated by performing predetermined image processing based on a plurality of original parallax images obtained from, for example, computer graphics or a real image. You. In this case, the actual parallax original image can be obtained by moving an imaging device such as one video camera around the subject. The image displayed on the display means such as a liquid crystal light valve is
It can be obtained by performing image processing based on the original parallax image captured by a video camera or the like.
d Dice ”. This "Sl
As shown in FIG. 15, the image processing by “ice and Dice” divides each of the plurality of original parallax images 61 into a slit shape in the parallax direction (the w direction in FIG. The image is reconstructed into a single image 60. This has the effect of correcting distortion peculiar to HS, which is only horizontal parallax, and reducing blur by bringing a three-dimensional image of the subject onto the hologram.

The image pickup apparatus according to the present embodiment uses the above-described HPO
It is used for capturing a parallax original image in the pattern one-step HS. Conventionally, as described above, the shooting of the original parallax image is
For example, one video camera is moved around a subject, but the imaging apparatus according to the present embodiment includes a plurality of area sensors 11 so that different parallaxes can be performed without moving the apparatus. The subject images in the directions can be obtained at the same time. Conventionally, one video camera is moved around a subject to capture a plurality of original parallax images, and thus the obtained plurality of original parallax images do not have real-time properties.

In the first embodiment, the output signals from the plurality of area sensors 11 are output to the digital signal processor 3.
4, the image data is finally output, for example, as image data of a single frame. However, in this embodiment, the output signals from the plurality of area sensors 11 are output. , A plurality of image data are generated and output in the digital signal processing unit 34. As a result, it is possible to acquire a plurality of original parallax images having real-time properties, which was impossible in the related art.

As described above, according to the imaging apparatus of the present embodiment, the digital signal processing section 34 generates and outputs a plurality of image data based on the output signals from the plurality of area sensors 11. So, HS
Can be obtained in real time.

Other configurations, operations, and effects of the present embodiment are the same as those of the first embodiment.

[Fifth Embodiment] Next, a fifth embodiment of the present invention will be described.
An embodiment will be described. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

The imaging apparatus according to the present embodiment is used to generate image data for integral photography using holography. Integral photography is a three-dimensional photography method originally proposed by MGLippmann. Hereinafter, an imaging method of integral photography using the imaging device of the present embodiment will be described.

FIG. 16 is an explanatory diagram showing an example of a configuration for realizing integral photography in the present embodiment. In order to realize integral photography, in the present embodiment, an imaging device 10A for imaging the subject 71, and the imaging device 10A is connected to the imaging device 10A by a plurality of connection lines 73, and is captured by the imaging device 10A. And a display 70 for displaying an image of the subject 71. The basic configuration of the imaging device 10A is the same as that of the imaging device 10 of the first embodiment. However, in the first embodiment, the output signals from the plurality of area sensors 11 are subjected to predetermined image processing in the digital signal processing unit 34, so that the output signals finally become, for example, single-frame image data. Although output is performed, in the present embodiment, a plurality of image data is generated and output by the digital signal processing unit 34 based on output signals from the plurality of area sensors 11.

In the present embodiment, an image of the subject 71 is formed on each of the plurality of area sensors 11 of the image pickup device 10A and is picked up. Here, a subject image formed on each of the plurality of area sensors 11 is called an element image. In the imaging device 10A, a plurality of signals corresponding to a subject image are output from the plurality of area sensors 11, and predetermined image processing is performed in the digital signal processing unit 34 based on the plurality of output signals, and a plurality of signals are output. Image data of the element image is generated and output. The image data of the plurality of element images is displayed on the display 70 by the plurality of connection lines 73.
Is transmitted to In the display 70, the imaging device 10A
Are displayed based on the conditions corresponding to the time of imaging. By the light from the group of element images displayed by the display 70 so as to correspond to the conditions at the time of imaging, a stereoscopic image is reproduced at a position corresponding to the object at the time of imaging. Therefore, a reproduced stereoscopic image can be observed in real time.

As described above, according to the imaging apparatus 10 A of the present embodiment, the digital signal processing section 34 generates and outputs a plurality of image data based on the output signals from the plurality of area sensors 11. As a result, image data for integral photography can be easily obtained.

The other configurations, operations, and effects of this embodiment are the same as those of the first embodiment.

The present invention is not limited to the above embodiments, and various modifications can be made. For example, in each of the above embodiments, the micro lens 2a has a structure having a curvature on only one surface, but the structure of the micro lens 2a may be a structure having a plurality of lens surfaces. Further, the microlens 2a may be configured to have a telescope type optical characteristic.

FIG. 17 and FIG.
13 shows another example of the configuration a. The micro lens 2a shown in FIG. 17 has one surface 81 (surface on which light from a subject enters) having a convex lens surface and the other surface 82 having a concave lens surface. It is an example configured to have the following optical characteristics. In this case, as compared with the case where only one surface has a curvature, for example, there is an advantage that it becomes easier to perform aberration correction and optical performance can be improved. The microlens 2a shown in FIG. 18 has one surface 83 (the surface on which light from a subject enters) having a convex lens surface and the other surface 84 having a convex lens surface. This is an example in which it is configured to have a telescope type optical characteristic.

[0069]

As described above, claims 1 to 1
According to the imaging device of any one of the first to third aspects, a signal corresponding to light from a subject is independently output by each of the plurality of imaging elements that are electrically independently driven, By using a plurality of optical systems provided at positions corresponding to a plurality of image sensors, light from a subject is incident on the plurality of image sensors with unique optical characteristics. It is possible to provide an additional effect, and it is possible to reduce the thickness of the device.

According to the image pickup apparatus of the fourth aspect,
Since the plurality of image sensors are driven at different timings and output signals corresponding to light from the subject at different timings, for example, a high-speed There is an effect that shooting can be realized.

Further, according to the imaging device of the eighth aspect,
At least one of the plurality of optical systems is configured such that light from a subject is incident on the plurality of imaging elements at a different focal length or imaging angle of view from the other. For example, a mechanical lens moving mechanism is used. There is an effect that it is possible to realize a focus adjustment function and a zoom function without the need.

Further, according to the imaging device of the ninth aspect,
Since a plurality of optical systems are configured so that the respective subject images formed on the plurality of image sensors are shifted from each other by a predetermined amount, a plurality of subject images shifted from each other are formed. Thus, it is possible to increase the resolution by synthesizing the output signals from the image pickup device.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a structural example of an imaging device according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a structure of a support substrate in the imaging device shown in FIG.

FIG. 3 is a plan view illustrating a structure of a microlens array in the imaging device illustrated in FIG. 1;

FIG. 4 is an explanatory diagram for describing optical characteristics of an optical system in the imaging device illustrated in FIG. 1;

FIG. 5 is an explanatory diagram illustrating a configuration example of an area sensor in the imaging device illustrated in FIG. 1;

FIG. 6 is a block diagram illustrating a circuit configuration of the imaging device illustrated in FIG. 1;

FIG. 7 is an explanatory diagram for describing an image processing technique of the imaging device according to the first embodiment of the present invention.

FIG. 8 is another explanatory diagram for describing the image processing technique of the imaging device according to the first embodiment of the present invention.

FIG. 9 is still another explanatory diagram for describing the image processing technique of the imaging device according to the first embodiment of the present invention.

FIG. 10 is an explanatory diagram for explaining a technique of expanding a dynamic range in the imaging device according to the first embodiment of the present invention.

FIG. 11 is an explanatory diagram for describing a function of high-speed shooting in the imaging device according to the first embodiment of the present invention.

FIG. 12 is an explanatory diagram illustrating a configuration example of an imaging device according to a second embodiment of the present invention.

FIG. 13 is an explanatory diagram illustrating a configuration example of an imaging device according to a third embodiment of the present invention.

FIG. 14 is an explanatory diagram for describing features of an imaging device according to a third embodiment of the present invention.

FIG. 15 is an explanatory diagram for explaining a holographic stereogram in which an imaging device according to a fourth embodiment of the present invention is used.

FIG. 16 is an explanatory diagram showing an integral photography technique in which an imaging device according to a fifth embodiment of the present invention is used.

FIG. 17 is an explanatory diagram illustrating another configuration example of the microlens in the imaging device of the present invention.

FIG. 18 is an explanatory diagram showing still another configuration example of the microlens in the imaging device of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Support substrate, 2 ... Micro lens array, 2a ... Micro lens, 3 ... Light shielding plate, 10 ... Image pickup device, 11 ... Area sensor, 31 ... Timing generation circuit, 34 ... Digital signal processing part.

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 4M118 AA02 AA10 AB01 BA13 CA03 CA26 DB01 FA06 FA13 FA26 GC11 GD03 HA22 HA24 5C022 AA14 AB23 AB28 AB36 AB68 AC42 AC54 AC69 5C024 AA01 CA11 CA15 CA26 EA04 EA08 FA01 FA11 GA16 HA07 HA09 HA14 HA18 HA20 HA24 5C061 AA08 AB06

Claims (11)

[Claims] 1. A plurality of image sensors each of which is electrically independently driven, each independently outputs a signal corresponding to light from a subject, and a plurality of image sensors corresponding to each of the plurality of image sensors. And a plurality of optical systems, each of which is provided at a position, and which causes light from a subject to enter the plurality of imaging elements with unique optical characteristics. 2. An image signal processing means for generating and outputting at least one predetermined unit of image signal based on a plurality of output signals from the plurality of image pickup devices. The imaging device according to 1. 3. The image pickup apparatus according to claim 2, wherein said image signal processing means performs image processing according to an external command to generate said image signal. 4. The imaging apparatus according to claim 1, wherein the plurality of imaging elements are driven at different timings and output signals corresponding to light from a subject at different timings. 5. The imaging apparatus according to claim 1, wherein an independent electronic shutter operation with a different exposure time can be performed for each of the plurality of imaging elements. 6. The imaging apparatus according to claim 1, wherein the plurality of optical systems include a plurality of microlenses arranged to face each of the plurality of imaging elements. 7. The imaging apparatus according to claim 1, wherein at least one of said plurality of optical systems is provided with an infrared ray removing means for selectively removing infrared light. 8. At least one of the plurality of optical systems,
The imaging apparatus according to claim 1, wherein light from a subject is incident on the plurality of imaging elements at a focal length or an imaging angle of view different from others. 9. The plurality of optical systems are configured so that respective subject images formed on the plurality of image pickup devices are formed with a predetermined amount of shift from each other. The imaging device according to 1. 10. The imaging apparatus according to claim 1, wherein a plurality of image data for holographic stereogram using holography is generated based on a plurality of output signals from the plurality of imaging elements. . 11. The imaging apparatus according to claim 1, wherein a plurality of image data for integral photography using holography is generated based on a plurality of output signals from the plurality of imaging elements. .