JP2004096633A - Imaging device and imaging method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging technique which prevents signal saturation in white balance processing with an improved signal-to-noise ratio (SNR) of an image signal. <P>SOLUTION: An imaging apparatus includes an imaging sensor, in which high sensibility to R (red) and B (blue) is set, so as to improve the SNR of the image signal. Under a light source of 2,850K, since an R channel (Rch) signal level becomes large in the imaging sensor, an imaging operation points of the entire (RGB) channels are decreased by AE (auto exposure) control. With this, the gain in the Rch is not decreased in the white balance processing. Similarly, under a light source of 10,000K, since a B channel (Bch) signal level becomes large in the imaging sensor, the imaging operation points of the entire (RGB) channels are also decreased by the AE control. As a result, the signal saturation in the white balance processing can be prevented, and also the SNR of the imaging signal can be improved. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an imaging technique using an imaging unit that has a single-plate pixel array in which filters of a plurality of colors are arranged and generates an output signal related to a subject.
[0002]
[Prior art]
The size of digital cameras (imaging devices) has been remarkably reduced, and there is a great demand in the market for higher sensitivity. For this reason, the pixel size of the image sensor has become smaller and the dynamic range has a tendency to be sacrificed. Further, in order to achieve high sensitivity, the sensitivity increase rate in an image processing circuit or the like is large, and there is a problem of deterioration of SN.
[0003]
In particular, with regard to color, in the case of a digital camera, it is necessary to correspond to an illumination light source having a color temperature of about 2850K to 10000K, and amplification factors for white balance correction of RGB greatly differ for each light source. For example, as shown in FIG. 10, when the spectrum is biased under a light source with a color temperature of 2850K or under a light source with a color temperature of 10000K, the WB gain increases for a specific color channel, so that the SN degradation of the image signal decreases Become noticeable.
[0004]
Therefore, as a method of improving the SN ratio of an image signal in consideration of these light sources, there is a method of increasing the sensitivity of R (red) and B (blue) in the image sensor.
[0005]
Further, for example, in Patent Document 1, by adjusting the signal level of each color before inputting a signal output from an image sensor to an A / D converter, image degradation due to quantization noise in white balance processing is reduced. Techniques for suppressing are disclosed.
[0006]
[Patent Document 1]
JP 2001-309393 A
[Problems to be solved by the invention]
However, in the above method of increasing the sensitivity of the image sensor, the sensitivity is increased with respect to R and B. Therefore, as illustrated in FIG. 11, for example, as illustrated in FIG. The signal saturation occurs in the channel that has occurred, and coloring phenomena Q1 and Q2 in which highlight portions are clipped occur.
[0008]
Further, when the technique of Patent Document 1 is applied, although the above-described signal saturation is improved, a circuit for extracting each color signal before A / D conversion is required, and the configuration of the digital camera is complicated.
[0009]
The present invention has been made in view of the above problems, and has as its first object to provide an imaging technique capable of preventing signal saturation in white balance processing and improving the SN ratio of an image signal.
[0010]
A second object of the present invention is to realize an imaging device having such advantages without using a complicated configuration.
[0011]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 is an imaging apparatus, which comprises: (a) an imaging apparatus having a single-pixel array in which filters of a plurality of colors are arrayed and generating an output signal relating to a subject; Means, (b) obtaining means for obtaining white balance information relating to the subject, and (c) an operating point for changing exposure control according to the white balance information and controlling an operating point of the output signal to a predetermined level. Control means.
[0012]
Further, according to a second aspect of the present invention, in the imaging device according to the first aspect of the present invention, (d) an analog amplifying means for amplifying the output signal to generate an amplified signal, and (e) digitally converting the amplified signal. Conversion means for generating a digital signal; and (f) digital amplifying means for amplifying the digital signal for each of the plurality of colors to generate an image output signal, wherein an operating point of the image output signal is provided. Is adjusted by changing the gain of the analog amplifier and / or the gain of the digital amplifier.
[0013]
According to a third aspect of the present invention, in the imaging device according to the first or second aspect, (g) the state in which the operating point control means is activated and the operating point control means are disabled. And a switching unit for switching between the state and the state.
[0014]
Further, the invention according to claim 4 is an imaging apparatus, wherein (a) an imaging means having a single-plate pixel array in which filters of a plurality of colors are arranged, and generating an output signal related to a subject; (C) a signal for adding a value obtained by multiplying an output signal for each color by a weighting coefficient set for each color of the plurality of colors to generate a luminance signal; And (c-1) changing means for changing the weighting coefficient according to the white balance information.
[0015]
Further, according to a fifth aspect of the present invention, there is provided an imaging method using an imaging device having a single-pixel array in which filters of a plurality of colors are arrayed, and having an imaging unit that generates an output signal related to a subject and an imaging optical system. (A) an obtaining step of obtaining white balance information on the subject; (b) a changing step of changing spectral characteristics of the imaging optical system according to the white balance information; Controlling the exposure point according to the white balance information and controlling the operating point of the output signal to a predetermined level.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
<First embodiment>
<Main components of imaging device>
FIG. 1 is a diagram showing functional blocks of an imaging device 1A according to the first embodiment of the present invention.
[0017]
The imaging device 1A is configured as a digital camera, and includes an imaging sensor 11, a signal processing unit 2 connected to the imaging sensor 11 so that data can be transmitted, an image processing unit 3 connected to the signal processing unit 2, and an image processing unit. 3 and a camera control unit 40 connected to the camera control unit 3.
[0018]
The imaging sensor 11 is configured as an area imaging sensor having a single-plate pixel array in which R (red), G (green), and B (blue) primary color transmission filters are arranged in a checkered pattern, and is an all-pixel readout type. It has become. In the image sensor 11, when the accumulation of the electric charge is completed, the photoelectrically converted signal is shifted to a light-shielded transfer path, from which the signal is read via a buffer, and an image signal relating to the subject is output.
[0019]
FIG. 2 is a diagram for explaining the spectral sensitivity characteristics of the image sensor 11. The horizontal axis in FIG. 2 indicates the wavelength, and the vertical axis indicates the sensitivity.
[0020]
The imaging sensor 11 has a spectral sensitivity characteristic including a sensitivity SR of the R channel (Rch), a sensitivity SG of the G channel (Gch), and a sensitivity SB of the B channel (Bch). Here, the sensitivity SR of Rch and the sensitivity SB of Bch are set to be higher than the sensitivity SRc of Rch and the sensitivity SBc of Bch of the conventional imaging sensor of FIG. As a method of setting such high sensitivity, there is a method of increasing the impurity concentration of the R pixel and the B pixel in the light receiving portion of the image sensor 11 or changing the characteristics of the red and blue filters of the image sensor 11.
[0021]
Returning to FIG. 1, the description will be continued.
[0022]
The signal processing unit 2 has a CDS 21, an AGC 22, and an A / D conversion unit 23.
[0023]
The image signal output from the image sensor 11 is sampled by the CDS 21 to remove noise of the image sensor 11 and then subjected to sensitivity correction by the AGC 22.
[0024]
The A / D converter 23 is configured by a 14-bit AD converter, and digitizes the analog signal normalized by the AGC 22. From the digitized image signal, an image file subjected to predetermined image processing by the image processing unit 3 is generated.
[0025]
The image processing unit 3 has a CPU and a memory, and includes a digital processing unit 30, an image compression unit 37, a video encoder 36, and a memory card driver 38.
[0026]
The digital processing unit 30 includes a pixel interpolation unit 31, a resolution conversion unit 32, a white balance control unit 33, a gamma correction unit 34, and a matrix calculation unit 35.
[0027]
The image data input to the image processing unit 3 is written to the image memory 41 in synchronization with the reading of the image sensor 11. Thereafter, the image data stored in the image memory 41 is accessed, and various processes are performed by the digital processing unit 30.
[0028]
The image data in the image memory 41 is obtained by masking each of the R, G, and B pixels with the respective filter patterns in the pixel interpolator 31 and then using a median (intermediate value) filter to calculate the average value of the intermediate binary values of the surrounding four pixels for the G pixels Replace. The average interpolation is performed for the R pixel and the B pixel.
[0029]
In the pixel-interpolated image data, the white balance (WB) control unit 33 performs gain correction for each of the R, G, and B pixels independently, and performs R, G, and B white balance correction. In this white balance correction, a portion that is originally white from a photographing subject is estimated from luminance, saturation data, and the like, and the average value of each of R, G, and B and the G / R, G / B ratio of the portion are obtained. Are controlled as R and B correction gains based on these information (white balance information).
[0030]
The image data subjected to the white balance correction is subjected to a non-linear conversion suitable for each output device by the gamma correction unit 34, and is converted into 8-bit data. Thereafter, Y, RY, and BY data are calculated from RGB by the matrix calculation unit 35 and stored in the image memory 41.
[0031]
Then, the Y, RY, and BY data stored in the image memory is subjected to horizontal / vertical reduction or thinning to the number of pixels set by the resolution conversion unit 32, and compression processing is performed by the image compression unit 37. After that, the data is recorded on the memory card 9 mounted on the memory card driver 38.
[0032]
The resolution conversion unit 32 also performs pixel thinning for image display, and creates a low-resolution image to be displayed on the LCD monitor 42 and the electronic viewfinder 43. At the time of preview, the low-resolution image of 640 * 240 pixels read from the image memory 41 is encoded by the video encoder 36 into NTSC / PAL, and is used as a field image as a field image in the LCD monitor 42 or the electronic viewfinder. At 43, image reproduction is performed.
[0033]
The camera control unit 40 includes a CPU and a memory, and processes an operation input performed by a photographer on a camera operation switch 49 having a shutter button and the like. By a photographer's operation input to the camera operation switch 49, a color image output mode for outputting a subject image as a color image and a monochrome image output mode for outputting a monochrome image can be selected.
[0034]
In the imaging apparatus 1A, the optical aperture value of the shutter 44 is fixed to the open state by the aperture driver 45 at the time of live view display in which the subject is displayed in a moving image manner on the LCD monitor 42 or the like before the main shooting. The charge accumulation time of the image sensor 11 is calculated as exposure control data by the camera control unit 40 based on light amount data measured in a photometry area selected from images acquired by the image sensor 11. Then, the feedback control is performed by the timing generator sensor driver 46 so that the exposure time of the image sensor 11 becomes appropriate by the program diagram preset based on the exposure control data calculated by the camera control unit 40.
[0035]
<About signal operating point of white balance processing>
FIG. 3 is a diagram for explaining signal operating points in white balance processing. This figure shows the state of the signals of each unit from the image sensor 11 to the white balance control unit 33, and the graphs D1 to D10 show the operation levels of the density (luminance) signal with respect to the dynamic range of each unit. Bold lines in the graphs D1 to D10 indicate operating points corresponding to white portions in the subject.
[0036]
The gain of the image signal photoelectrically converted by the image sensor 11 and sampled by the CDS 21 is increased according to the camera sensitivity set by the AGC 21 of the analog amplifier. As a result, the operating point (thick line portion) rises from the graphs D1 and D2 to the graph D3. At this time, since the image signal is composed of the Bayer signal from the image sensor 11, the gain is uniformly applied to RGB.
[0037]
The analog image signal gained by the AGC 22 is converted into a 14-bit digital signal by the A / D converter 23 with respect to the full range of the output of the AGC 22.
[0038]
Since the digital signals generated by the A / D converter 23 are arranged in a signal array composed of an RGB Bayer array, the pixel interpolator 31 converts the digital signals into RGB three-channel data as shown in graphs D5 to D7. Separate and interpolate.
[0039]
The RGB three-channel image signal generated by the pixel interpolation unit 31 normalizes the levels of the R signal and the B signal with respect to the G signal in the WB control unit 33, and performs RGB operations on a white subject as shown in graphs D8 to D10. Match points.
[0040]
As described above, the signal is amplified by the AGC 22 functioning as the analog amplifier and amplified by the WB controller 33 functioning as the digital amplifier, so that the operating point of the image signal can be adjusted and appropriate white balance processing can be performed. .
[0041]
<Operation of imaging apparatus 1A>
When the color image output mode is selected in the imaging apparatus 1A, the imaging sensor 11 in which the Rch and the Bch are set to high sensitivity is employed. Therefore, in order to prevent highlight coloring shown in FIG. Perform the operation described.
[0042]
FIG. 4 is a diagram for describing white balance processing in the imaging device 1A. 4A to 4I, graphs Ga to Gi on the left side represent operating points of the image sensor 11, that is, signal levels photoelectrically converted in the pixel array, and graphs Ha to Hi on the right side represent the WB control unit 33. And the numerical value in the rectangle indicates the WB gain. In the graphs Ga to Gi and Ha to Hi, the lower part shows the signal distribution of a reflective object including the main object, and the upper part shows the signal distribution of a bright object such as a light source.
[0043]
4 (b), (e) and (h) show operating point distributions of Rch, Gch and Bch under a light source of 5000K which is a common light source. To normalize with G, that is, perform white balance control, a gain of 1 dB is applied to Rch and Bch as shown in FIGS. 4B and 4H. Here, since the RGB balance is improved by increasing the sensitivity of Rch and Bch, an image having a small RGB gain ratio (WB gain) and a good SN ratio can be generated.
[0044]
FIGS. 4A, 4D, and 4G show operating point distributions of Rch, Gch, and Bch under a light source of 2850K, respectively. 2), the signal level of the entire imaging operation point, that is, the signal level of all channels of the imaging sensor 11 is lowered. That is, the operating point of each channel in the image sensor 11 is lowered by lowering the target value of Gch, which is the reference of the AE control, by 2 dB lower than usual. As a result, in the WB control unit 33, the gain increases by 6 dB in Bch and 2 dB in Gch, but does not decrease by 0 dB in Rch. That is, by controlling the operating point of the output signal of the image sensor 11 to a predetermined level by the AE control (exposure control), it is not necessary to reduce the gain in Rch shown in FIG. It will be.
[0045]
FIGS. 4C, 4F, and 4I show operating point distributions of Rch, Gch, and Bch under a light source of 10000K, respectively, and FIG. In order to avoid the occurrence of the data clip as shown in (2), the entire imaging operation point is lowered as in the case of the light source at 2850K. Thereby, in the WB control unit 33, the gain is 6 dB for Rch and 2 dB for Gch, but is 0 dB for Bch and there is no gain down. That is, the gain reduction in Bch shown in FIG. 11I becomes unnecessary, and the problem of coloring is eliminated.
[0046]
In the imaging apparatus 1A, in the case of 2850K or 10000K, that is, when the light source spectrum is biased toward red or toward blue, the effective sensitivity set to, for example, ISO100 is changed as shown in FIG. Although the AE control for lowering the light source is performed, the estimation of the light source spectrum is performed based on the control data in the WB control unit 33, that is, the white balance information.
[0047]
That is, the known light source spectrum at 2850K or 10000K is stored as reference information in a memory in the imaging apparatus 1A, and the white balance information obtained for the subject is compared with the above-described reference information, thereby obtaining the light source spectrum of the subject. Is estimated to correspond to a specific color temperature such as 2850K or 10000K, and when the color temperature of the subject corresponds to the vicinity of the specific color temperature, the effective sensitivity is reduced. Performs exposure control operation. Then, while performing such exposure control based on the white balance information, the operating point of the output signal is changed by changing the gain of the analog amplifier (AGC 22) and / or the gain of the digital amplifier (WB control unit 33). Thus, by adjusting to a predetermined level, the signal-to-noise ratio of the output signal can be improved while preventing signal saturation. In this configuration, a circuit for extracting and processing each color signal before A / D conversion as described in Patent Literature 1 is unnecessary.
[0048]
By operating the imaging apparatus 1A as described above, the operating point of the imaging sensor 11 is not fixed based on Gch, and the operating point of each channel is entirely reduced by AE control according to the light source spectrum. Highlight coloring under a light source that is biased toward the light source can be prevented. In addition, since the image sensor 11 with increased Rch and Bch sensitivity is used, the gain balance of RGB becomes substantially equal, particularly under a common light source, and noise deterioration due to WB gain can be suppressed.
[0049]
When the monochrome image output mode is selected in the imaging device 1A, a monochrome image is generated using a Y signal that is close to normal visibility. This Y signal (luminance signal) is generated by adding a value obtained by multiplying the output signal of the image sensor 11 for each color by a weighting coefficient set for each color of RGB, and is a signal of only gray density gradation. .
[0050]
In this case, the imaging device 1A employs the imaging sensor 11 in which Rch and Bch are set to high sensitivity, and changes the entire imaging operation point according to the light source spectrum by the AE control. As shown in FIG. 4 (f), the operating point of Gch dominant to the Y signal is changed, and noise degradation of Gch also occurs.
[0051]
Therefore, in order to suppress noise deterioration during monochrome shooting, the RGB addition coefficient when generating the Y signal is changed in conjunction with the light source spectrum estimated from the WB gain calculated by the white balance control unit 33. Thus, a monochrome signal having a good SN can be obtained by avoiding excessive gain increase.
[0052]
Specifically, when the light source spectrum is 2850K, 5000K, and 10000K, a Y signal calculation equation (weighted sum) having RGB addition coefficients as shown in the following equations (1) to (3) is used.
[0053]
(1) 2850K;
Y = 0.48 * R + 0.47 * G + 0.05 * B (1):
(2) 5000K;
Y = 0.3 * R + 0.59 * G + 0.11 * B (2):
(3) 10000K;
Y = 0.15 * R + 0.47 * G + 0.38 * B (3):
By the operation of the imaging device 1A as described above, the calculation formula of the Y signal is changed according to the light source spectrum to generate a monochrome image. By suppressing the addition coefficient of the color channel, the SN ratio of the monochrome image can be appropriately adjusted.
[0054]
<Second embodiment>
<Main components of imaging device>
FIG. 6 is a diagram illustrating functional blocks of an imaging device 1B according to the second embodiment of the present invention.
[0055]
The imaging device 1B is also configured as a digital camera, and has a configuration similar to that of the imaging device 1A according to the first embodiment, except that a filter unit 5 is provided in front of the imaging sensor 11 and an external The difference is that the attachment filter FL can be attached.
[0056]
The filter unit 5 includes two types of infrared cut filters (built-in filters) and a filter switching unit.
[0057]
The two types of infrared cut filters include an infrared light absorption type filter having a characteristic Fa shown in FIG. 7A and a vapor deposition type sharp cut filter having a characteristic Fb shown in FIG. These two types of built-in filters are switched by a filter switching unit.
[0058]
Accordingly, when the infrared light absorption type filter is set in front of the imaging sensor 11, the infrared light absorption type filter has the Rch sensitivity PRa shown in FIG. 7B, and when the vapor deposition type sharp cut filter is set. , Rch sensitivity PRb shown in FIG. That is, when switching to the vapor deposition type sharp cut filter having the characteristic Fb, the sensitivity of Rch can be increased.
[0059]
<Operation of Imaging Device 1B>
The imaging device 1B has a configuration in which the sensitivity of Rch can be changed by switching between two types of built-in filters in the filter unit 5. The operation of the imaging device 1B when the built-in filters are switched will be described.
[0060]
When the photographer operates the camera operation switch 49 and selects the vapor deposition type sharp cut filter having the characteristic Fb in the filter unit 5, the imaging sensor 11 has the Rch sensitivity PRb shown in FIG. 7B. Accordingly, as shown in FIG. 4, the operation mode is set to the operation point changing mode for preventing highlight coloring by lowering the entire imaging operation point. That is, the operating point control means is activated, and appropriate white balance processing is performed.
[0061]
Further, when the photographer switches to the Rch sensitivity PRa shown in FIG. 7B and selects the infrared light absorption type filter, the above-mentioned operating point control means is disabled, and as shown in FIG. The white balance processing is performed in the operation point invariable mode in which the imaging operation point is not changed.
[0062]
By the operation of the imaging device 1B as described above, the sensitivity of Rch can be increased, and the same effect as in the first embodiment can be obtained. Further, since the operation point change mode and the operation point invariable mode are switched with the filter switching, white balance processing intended by the photographer can be performed.
[0063]
Further, in the image pickup apparatus 1B, not only the two types of built-in filters are switched in the filter unit 5, but also the type Fr of the external filter is displayed on the LCD monitor 42 as shown in FIG. May be prompted to the photographer.
[0064]
In this case, it is preferable to display the recommended type of the external filter on the LCD monitor 42 based on the relationship between the color temperature shown in FIG. 9 and the type of the external filter to be mounted. That is, the spectral characteristic of the imaging optical system is changed according to the color temperature estimated from the white balance information. Here, when an external filter is attached, control in the above-described operating point change mode is performed. As a result, a plurality of types (four types in the illustrated example) of the filters can be appropriately switched, and the SN ratio can be appropriately improved at each color temperature.
[0065]
<Modification>
The specific embodiments described above include inventions having the following configurations.
[0066]
(1) An imaging apparatus comprising: display means; and display control means for displaying information of a color filter to be mounted based on white balance information on the display means.
[0067]
This makes it possible to appropriately improve the SN ratio of the image signal.
[0068]
(2) An imaging apparatus comprising a change unit for changing the setting of the effective sensitivity.
[0069]
Thereby, signal saturation can be easily prevented.
[0070]
【The invention's effect】
As described above, according to the first to third aspects of the present invention, the exposure control is changed in accordance with the white balance information and the operating point of the output signal of the imaging means is controlled to a predetermined level. , Signal saturation can be prevented, and the SN ratio of the image signal can be improved. Further, since a circuit for extracting and processing each color signal before A / D conversion is unnecessary, the circuit configuration is not complicated.
[0071]
In particular, in the second aspect of the present invention, the operating point of the image output signal is adjusted by changing the gain of the analog amplifier and / or the gain of the digital amplifier, so that the white balance processing can be appropriately performed.
[0072]
According to the third aspect of the present invention, since the operating point control means is switched between a state in which the operating point control means is activated and a state in which the operating point control means is disabled, setting according to the photographer's intention is possible.
[0073]
According to the fourth aspect of the present invention, since the luminance signal is generated by changing the weighting coefficient set for each of the plurality of colors according to the white balance information, the SN ratio of the luminance signal can be improved.
[0074]
According to the fifth aspect of the present invention, the spectral characteristic of the imaging optical system is changed according to the white balance information, and the exposure control is changed to control the operating point of the output signal to a predetermined level. As a result, signal saturation can be prevented in the white balance processing, and the SN ratio of the image signal can be improved.
[Brief description of the drawings]
FIG. 1 is a diagram showing functional blocks of an imaging device 1A according to a first embodiment of the present invention.
FIG. 2 is a diagram for explaining spectral sensitivity characteristics of an image sensor 11;
FIG. 3 is a diagram for explaining signal operating points in white balance processing.
FIG. 4 is a diagram for explaining white balance processing in the imaging apparatus 1A.
FIG. 5 is a diagram showing a relationship between color temperature and effective sensitivity.
FIG. 6 is a diagram illustrating functional blocks of an imaging device 1B according to a second embodiment of the present invention.
FIG. 7 is a diagram for explaining spectral sensitivity characteristics of the imaging device 1B.
FIG. 8 is a diagram showing a manner of displaying the type of filter on an LCD monitor 42.
FIG. 9 is a diagram illustrating a relationship between a color temperature and a filter to be mounted.
FIG. 10 is a diagram for explaining white balance processing according to the related art of the present invention.
FIG. 11 is a diagram for explaining white balance processing according to the related art of the present invention.
[Explanation of symbols]
1A, 1B Imaging device 3 Image processing unit 11 Image sensor 31 Pixel interpolation unit 33 White balance control unit 40 Camera control unit 42 LCD monitors PRa, PRb, SR Sensitivity PG, SG G channel (Gch) sensitivity of R channel (Rch) PB, SB B channel (Bch) sensitivity

Claims (5)

An imaging device,
(A) an imaging unit that has a single-plate pixel array in which filters of a plurality of colors are arranged and generates an output signal related to a subject;
(B) obtaining means for obtaining white balance information relating to the subject;
(C) operating point control means for changing exposure control according to the white balance information and controlling an operating point of the output signal to a predetermined level;
An imaging device comprising: The imaging device according to claim 1,
(D) an analog amplifier for amplifying the output signal and generating an amplified signal;
(E) conversion means for digitally converting the amplified signal to generate a digital signal;
(F) digital amplifying means for amplifying the digital signal for each of the plurality of colors to generate an image output signal;
Further comprising
The image pickup apparatus according to claim 1, wherein an operating point of the image output signal is adjusted by changing an amplification factor of the analog amplification device and / or an amplification factor of the digital amplification device. In the imaging device according to claim 1 or 2,
(G) switching means for switching between a state in which the operating point control means is activated and a state in which the operating point control means is disabled;
An imaging device, further comprising: An imaging device,
(A) an imaging unit that has a single-plate pixel array in which filters of a plurality of colors are arranged and generates an output signal related to a subject;
(B) obtaining means for obtaining white balance information relating to the subject;
(C) signal generating means for generating a luminance signal by adding a value obtained by multiplying an output signal for each color by a weighting coefficient set for each color of the plurality of colors;
With
The signal generation means,
(C-1) changing means for changing the weighting coefficient according to the white balance information;
An imaging device comprising: An imaging method using an imaging apparatus including an imaging unit that generates an output signal related to a subject and an imaging optical system that includes a single-plate pixel array in which filters of a plurality of colors are arranged,
(A) an obtaining step of obtaining white balance information relating to the subject;
(B) a changing step of changing spectral characteristics of the imaging optical system according to the white balance information;
(C) a control step of changing exposure control according to the white balance information and controlling an operating point of the output signal to a predetermined level;
An imaging method, comprising:

Images