JP2000041180A - Imaging apparatus and adjustment method of imaging apparatus - Google Patents

Abstract

(57) Abstract: An imaging apparatus and an adjustment method of the imaging apparatus are applied to an imaging apparatus configured to record a moving image and a still image on a magneto-optical disk apparatus, for example, and are simple and reliable. To adjust the polarization filter. An adjustment amount is determined for a polarizing filter of an optical system that forms an optical image on a light receiving surface based on an imaging result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus and a method for adjusting the image pickup apparatus. The present invention makes it possible to easily and reliably adjust a polarizing filter of an optical system that forms an optical image on a light receiving surface by determining an adjustment amount based on an imaging result.

[0002]

2. Description of the Related Art Conventionally, in a television camera, a silver halide camera, or the like, a polarizing filter is arranged in front of a lens so that unnecessary external light can be shielded.

That is, a cameraman manually adjusts the rotation of the polarizing filter so as to obtain a desired image pickup result while visually confirming the image pickup result formed in the viewfinder. In the polarization filter, this rotation adjustment blocks incident light on a predetermined polarization plane, thereby, for example, when imaging a subject through glass, blocks light reflected by the glass, and in a landscape image, etc.
The contrast can be further improved.

[0004]

By the way, the adjustment of this kind of polarizing filter cannot be avoided by performing the adjustment manually, thereby causing a variation in the adjustment accuracy. In addition, in a television camera or the like, a sufficient resolution and gradation may not be assigned to a display unit that displays an imaging result, and an optimum adjustment position may not be correctly determined in some cases.

[0005] Thus, in the conventional imaging apparatus,
There is a problem that the operation of the polarizing filter is complicated and cannot be adjusted with sufficient accuracy.

The present invention has been made in view of the above points, and an object of the present invention is to propose an image pickup apparatus and an image pickup apparatus adjustment method capable of easily and surely adjusting a polarizing filter.

[0007]

According to the present invention, in order to solve the above-mentioned problems, an image pickup apparatus is provided with a judging means for judging an adjustment amount of a polarizing filter based on an image pickup result.

In the adjusting method of the image pickup apparatus, an adjustment amount is determined for a polarizing filter of an optical system that forms an optical image on the light receiving surface based on a result of capturing an optical image formed on the light receiving surface.

If the adjustment amount of the polarizing filter of the optical system that forms the optical image on the light receiving surface is determined based on the imaging result obtained according to the optical image, the polarizing filter is manually adjusted as necessary according to the determination result. Or can be adjusted automatically, and the adjustment accuracy can be further improved.

[0010]

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

(1) First Embodiment (1-1) Configuration of First Embodiment FIG. 2 is a perspective view showing a video camera according to a first embodiment of the present invention. The video camera 1 is entirely formed in a rectangular shape having a small thickness, and a camera lens 2 having a lens group, an aperture, and the like for photographing is disposed on the front surface thereof. In the video camera 1, a liquid crystal display unit 3 for monitoring an imaging result is formed on an upper surface portion.
, An operator 4 for starting / stopping recording and a standby switch 5 for setting the entire operation mode to a recordable state are arranged.

In the video camera 1, the rear of the camera lens 2 is assigned to a camera unit 6. After processing the image pickup result by the camera unit 6, an electronic viewfinder 7 behind the camera lens 6 is processed.
Display by

In the video camera 1, a disk slot 8 is disposed on the back, and a cartridge 9 containing a magneto-optical disk as a recording medium of an image pickup result is inserted into the disk slot 8. Here, this magneto-optical disk is
An MD-DATA2 format mini-disc is used, and the imaging result is recorded as a moving image or a still image.

The video camera 1 is configured so that sound acquired by a microphone can be recorded on the magneto-optical disk, and the sound acquired by the microphone and the recorded sound can be confirmed by a speaker.

FIG. 3 is a schematic diagram showing a track shape of a magneto-optical disk according to the MD-DATA2. This M
In the magneto-optical disk of D-DATA2, a pair of grooves NWG and WG serving as a guide groove for a laser beam are spirally formed on the information recording surface from the inner peripheral side to the outer peripheral side (so-called double spiral).

Further, in the magneto-optical disk of MD-DATA2, the pair of grooves NWG and WG are
It is formed narrower than the WG and the land Ld between the WGs,
Thus, land recording can be performed. Further, the magneto-optical disk of MD-DATA2 is formed so that one groove WG of the pair of grooves NWG and WG is meandering, and the common positional information about the lands Ld on both sides of the groove WG is meandering. (So-called interlace addressing method).

As a result, in the magneto-optical disk of MD-DATA2, the A track TrA, which is a groove WG and a non-serpentine groove NWG on the outer peripheral side and the inner peripheral side, respectively, and the outer peripheral side and the inner peripheral side are not meandering, respectively. A double track is formed by the groove NWG and the B track TrB which is the meandering groove WG.

As a result, when the MD-DATA2 magneto-optical disk is partially enlarged and irradiated with a light beam by, for example, a three-beam method as shown by an arrow A, any of the side spots SPsl or SPs2 meanders. Groove N
These side spots SPsl determine whether the WG is being scanned.
By making a determination based on the result of receiving the return light by SPs2 and SPs2, the track on which the main beam spot SPm is scanning can be determined, and furthermore, position information can be obtained from meandering.

As a result, the MD-DATA2 magneto-optical disk can reduce the track pitch by suppressing the crosstalk between wobbles. Here, the groove WG meanders according to the signal level of a modulation signal generated by bi-phase mark modulation and frequency modulation of the position information, and the track pitch Tp is 0.95 [μm]. .

FIG. 4 shows an MD-DATA in comparison with a conventional mini-disc format (MD-DATA1).
2 is a table showing a format of FIG. MD-DATA2
The format used was an optical system with a laser wavelength of 650 [nm] and an aperture ratio of 0.52, and a track pitch of 0.95.
Desired data is recorded by [μm] and bit length 0.39 [μm / bit]. As a recording method, a land recording method based on the above-described address method is adopted, an RLL (1, 7) modulation method is used as a modulation method, an RS-PC method is used as an error correction method, and a block complete data interleave is used. , 19.7 [%], desired data is recorded. As a driving method, a CLV with a linear velocity of 2.0 [m / s] is adopted, and a standard data rate is 589 [kB / s].

FIG. 5 is a block diagram showing the configuration of the MD block. The MD block 11 is provided in the video camera 1 on the magneto-optical disc 10 in the MD-DATA2 format or on the magneto-optical disc in the MD-DATA1 format. And the sound is recorded.

That is, in the MD block 11, the spindle motor 13 rotates the magneto-optical disk 10 by driving the servo driver 14 under the condition that the linear velocity is constant. The thread motor 15 causes the optical head 16 and the modulation coil 17 to seek in the radial direction of the magneto-optical disk 10 by driving the servo driver 14.

The optical head 16 irradiates a laser beam emitted from a built-in laser diode to the magneto-optical disk 10 via an objective lens (not shown), receives the returned light, and outputs a light reception result. At this time, the optical head 16 drives the objective lens by the servo driver 14 so that tracking control and focus control can be performed. At this time, as described above with reference to FIG. 3, the optical head 16 focuses the laser beam on the magneto-optical disk by the three-spot method. Further, the optical head 16 emits a laser beam with a predetermined light amount under the control of the laser driver 30, and intermittently starts up the laser beam light amount to a predetermined light amount from the light amount at the time of recording and reproduction, thereby outputting desired data. Thermomagnetic recording can be performed on the magneto-optical disk 10.

The matrix amplifier 19 includes the optical head 16
A matrix calculation process is performed on the light receiving result output from the light emitting device, and thereby a tracking error signal whose signal level changes according to the tracking error amount, a focus error signal whose signal level changes according to the focus error amount, and a meandering groove. The wobble signal whose signal level changes is output. At this time, the matrix amplifier 19
By generating a wobble signal from each of the two side spots formed on the magneto-optical disk, two systems of wobble signals corresponding to the two side spots are output.

The servo processor 20 drives the objective lens of the optical head 16 via the servo driver 14 so that the tracking error signal and the focus error signal output from the matrix amplifier 19 are at predetermined signal levels, respectively. To perform tracking control and focus control of the optical head 16. Further, the servo processor 20 drives the spindle motor 13 via the servo driver 14 in accordance with the instruction of the CLV processor 21, thereby controlling the rotation of the magneto-optical disk 10 under the condition of a constant linear velocity. Further, the servo processor 20 drives the sled motor 15 via the servo driver 14 under the control of the driver controller 22, thereby causing the optical head 16 to seek to a predetermined position. Thus, the servo driver 14 drives the spindle motor 13 and the like under the control of the servo processor 20.

ADIP band pass filter (BPF) 2
Reference numeral 3 denotes a band-limited output of two wobble signals output from the matrix amplifier 19, and the track detection circuit 24 monitors a change in signal level of the wobble signal output from the ADIP bandpass filter 23. As a result, a track determination signal indicating which of the A track and the B track the main spot is scanning is output. The ADIP decoder 25 performs signal processing on the wobble signal output from the ADIP bandpass filter 23, thereby detecting and outputting position information of a laser beam irradiation position.

The driver controller 22 is a microcomputer that controls the operation of the MD block 11 in accordance with data communication with a controller that controls the operation of the video camera 1 as a whole. According to the position information detected by the ADIP decoder 25, the CLV processor 2
1. A desired area of the magneto-optical disk 10 can be accessed by controlling the operation of the servo processor 20. Also, the operation of the recording / reproducing system is controlled as necessary, whereby the imaging result and the like obtained by the camera unit 6 are recorded on the magneto-optical disk 10, and the imaging result and the like recorded on the magneto-optical disk 10 are reproduced.

The CLV processor 21 generates rotational speed information of the spindle motor 13 necessary for driving the magneto-optical disk 10 under the condition of a constant linear velocity for the recording / reproducing position specified by the driver controller 22, and generates a servo processor. 20 operation is instructed. Further, at this time, the CLV processor 21 processes the wobble signal output from the ADIP bandpass filter 23 with reference to the clock output from the equalizer / PLL circuit 28, so that the signal level of the wobble signal changes at a predetermined frequency. To operate the servo processor 20.

The RF amplifier 27 amplifies, with a predetermined gain, a reproduced signal whose signal level changes in accordance with the polarization plane of the return light based on the light reception result output from the optical head 16, and outputs the amplified signal. / D) 31 performs an analog-to-digital conversion process on the reproduced signal RF with reference to a clock output from the equalizer / PLL circuit 28. Thus, the analog-to-digital conversion circuit 31 converts the reproduced signal into a digital reproduced signal having a predetermined number of bits and outputs the digital reproduced signal.

The AGC / clamp circuit 32 multiplies the digital reproduction signal by changing the coefficient so that the envelope of the digital reproduction signal obtained in this way has a predetermined signal level, and also performs the processing at the predetermined signal level. Output after clamping. The equalizer / PLL circuit 28 reproduces and outputs a clock from the digital reproduction signal output from the AGC / clamp circuit 32, and performs arithmetic processing to correct the frequency characteristics and the waveform characteristics.

The Viterbi decoder 33 has an equalizer / PL
By performing Viterbi decoding on the reproduction data output from the L circuit 28, output data of an RLL modulation circuit 34 described later is demodulated and output. The RLL demodulation circuit 35 demodulates the output data of the Viterbi decoder 33 by RLL (1, 7), thereby reproducing video data and audio data recorded on the magneto-optical disk 10 and outputting the reproduced data to the bus BUS.

The buffer memory 37 temporarily holds the video data and audio data reproduced data thus output to the bus BUS during reproduction and outputs the data to the bus BUS during recording. Video data and audio data to be temporarily recorded and output.

The ECC processing circuit 39 performs an error correction process on the video data and audio data reproduced data held in the buffer memory 37 during reproduction, and similarly stores the data in the buffer memory 37 during recording. An error correction code is generated and output for the video data and audio data obtained.

At the time of reproduction, the descrambling EDC decoder 40 inputs and outputs, in a predetermined order, the error-corrected reproduction data stored in the buffer memory 37, and descrambles the reproduction data. I do. At this time, the descrambling EDC decoder 40
An error detection process based on the EDC code is executed, and the video data and the audio data D2 are output to the camera unit 6.

At the time of recording, the scramble EDC encoder 41 receives video data and audio data D1 from the camera unit 6, and adds a code for error detection. Further, the scramble EDC encoder 41 scrambles the video data, the audio data D1, and the error detection code, and outputs them.

At the time of recording, the RLL modulating circuit 34 converts the video data and the audio data D1 added with the error correction code held in the buffer memory 37 into error detection codes.
They are sequentially input together with the error correction code, and are RLL (1, 7) modulated and output.

The laser driver 30 controls the operation of the optical head 16 so as to irradiate a laser beam with a constant light amount at the time of reproduction, but at the time of recording, according to the processing result of the RLL modulation circuit 34. The operation of the optical head 16 is controlled so as to intermittently raise the light amount of the laser beam according to the cycle of.

The modulation coil driving circuit 43 controls the modulation coil 17 according to the modulation data generated by the RLL modulation circuit 34.
, And the modulation coil 17 applies a modulation magnetic field having a polarity corresponding to the modulation data to the laser beam irradiation position of the optical head 16. Thereby, the MD block 11
Records the video data and audio data D1 from the camera unit 6 on the magneto-optical disk 10 by thermomagnetic recording.

FIG. 6 is a block diagram showing the camera section 6 of the video camera 1. The camera unit 6 outputs an imaging result by video data of a moving image or a still image, and outputs audio data of an audio to the MD block 11, and outputs video data and audio data D 2 as reproduction results output from the MD block 11. Process.

That is, in the camera section 6, the camera lens 2 converts the optical image of the subject into a CCD solid-state image pickup device 50.
Is formed on the light receiving surface. At this time, the aperture 2A of the camera lens 2 is driven by the driver 51, thereby forming an optical image by limiting the amount of incident light as necessary. The driver 52 moves the built-in lens along the optical axis, thereby changing the magnification of the optical image. Driver 5
3 changes the focal length, thereby enabling automatic focus adjustment.

Further, in the camera lens 2, as shown in FIG. 7, a polarizing filter 55 is arranged at a predetermined position of the optical system. Here, the polarizing filter 55 has a movable filter disposed on a ring 56 having a gear portion formed on the outer periphery, and the ring 56 can be driven to rotate by a motor 57. The camera lens 2 is configured such that the motor 57 can be driven by a driver 58, and as shown by an arrow B, the polarization filter 55 can be adjusted by a motor drive. In the camera lens 2, the polarization filter can be manually adjusted by a clutch (not shown).

The CCD solid-state imaging device 50 operates according to various reference signals generated by a timing generator (TG) 59, and outputs a result of capturing an optical image formed on a light receiving surface. The sample hold (S / H) AGC circuit 60
After performing correlated double sampling of the imaging result, the signal levels are corrected to generate and output red, blue, and green color signals.

Analog-to-digital conversion circuit (A / D) 6
1 performs analog-to-digital conversion processing of these red, blue, and green color signals, and outputs red, blue, and green digital color signals. The camera signal processing circuit 62 receives the digital color signal, performs correction processing such as gamma correction and knee correction, and then performs matrix operation processing, thereby generating and outputting a luminance signal and a color difference signal based on the digital signal. The camera shake correction circuit 63 performs camera shake correction, digital zoom processing on the luminance signal and color difference signal based on the digital signal output from the camera signal processing circuit 62, and outputs the result.

The image compression / expansion circuit 64 compresses the luminance signal and the color difference signal output from the camera shake correction circuit 63 at the time of recording and outputs it to the MD block 11, and at the time of reproduction, reverses the above. Then, the reproduction data D1 based on the video data output from the MD block 11 is decompressed and output to the display control circuit 65. The image compression / decompression circuit 64 outputs the luminance signal and the color difference signal output from the camera shake correction circuit 63 to the display control circuit 65 as they are, except during reproduction.

Here, when the user selects the recording mode for moving images, the image compression / decompression circuit 64
While the luminance signal and the color difference signal are data-compressed according to the two methods (ving Picture Experts Group), when the user selects the recording mode for still images, the JPEG (Jo
Int Photographic Coding Experts Group) compresses the luminance signal and the color difference signal. Thus, the video camera 1 can record the video data D1 generated by compressing the data on the magneto-optical disk. On the other hand, at the time of reproduction, the video data recorded on the magneto-optical disk can be reproduced by expanding the video data D2 reproduced according to the format at the time of recording.

The display control circuit 65 is constituted by a microcomputer which controls the operation of the camera unit 6 by data communication with the driver controller 22 of the MD block 11, and compresses various information obtained by the data communication into an image. The luminance signal and the color difference signal output from the expansion circuit 64 are superimposed and output.

Digital-to-analog conversion circuit (D / A) 6
6 performs a digital-to-analog conversion process on the luminance signal and the color difference signal output from the display control circuit 65, thereby outputting a luminance signal and a color difference signal based on the analog signal. The driver 67 drives the liquid crystal display unit 3 and the electronic viewfinder 7 based on the luminance signal and the color difference signal to form a display image. Thus, in the video camera 1, the imaging result and the reproduction result can be confirmed on the liquid crystal display unit 3, and the entire operation information can be visually confirmed.

The encoder 68 converts the luminance signal and the color difference signal into an NTSC video signal and outputs the video signal to an external device terminal.

The microphone 69 collects the sound of the subject and outputs the sound signal. The amplifier circuit 70 amplifies the audio signal output from the microphone 69 with a predetermined gain and outputs the amplified signal. The analog-to-digital converter (A / D) 71 performs analog-to-digital conversion processing on the audio signal output from the amplifier circuit 70. Output. The audio compression / expansion circuit 72 performs
The audio signal is compressed and output to the MD block 11 as audio data to be recorded. At the time of reproduction, on the contrary, the audio data output from the MD block 11 is decompressed and output. The audio compression / expansion circuit 72 is provided with an ATRAC (Adaptive Transform Aco
After the audio signal is band-divided by ustic coding, spectrum conversion is performed and data compression is performed.

Digital-to-analog conversion circuit (D / A) 7
3 performs digital-to-analog conversion processing on the audio data output from the audio compression / decompression circuit 72, and the amplification circuit 74 amplifies the audio signal and outputs the amplified audio signal from the speaker 75. This allows the video camera 1 to record the audio together with the imaging result and to listen to the recorded audio.

The camera controller 76 is constituted by a microcomputer that controls circuit blocks from the camera lens 2 to the image compression / expansion circuit 64. For example, by switching the operation of the timing generator 59 according to the shutter speed set by the operator, CCD
The charge accumulation time of the solid-state imaging device 50 is controlled. Further, the camera controller 76 integrates the luminance level of the luminance signal input from the camera signal processing circuit 62 in a predetermined area, inputs the integrated luminance level to the aperture control circuit 78, and
Controls the aperture 2A via the driver 51 so that the integration result becomes a predetermined value.

The camera controller 76 outputs control data to a pulse driver 79 in response to the operation of an operation member arranged close to the camera lens 2, and the pulse driver 79 outputs the control data via the driver 52. The imaging magnification of the camera lens 2 is changed in response to Further, the camera controller 76 extracts a high-frequency component having a frequency equal to or higher than a predetermined frequency from the luminance signal and integrates the signal level. The camera controller 76 outputs control data to the pulse driver 79 so as to switch the driving direction when the integration result starts to decrease. The pulse driver 79 responds to the control data via the driver 53 and controls the camera lens 2. Adjust the focus. As a result, the camera controller 76 executes an automatic focus adjustment process.

The camera controller 76 detects a luminance distribution from the luminance signal and outputs control data to the pulse driver 79 based on the detection result, thereby automatically controlling the polarization filter of the lens 2 via the pulse driver 79. Adjust to

FIG. 1 is a flowchart showing the procedure of the automatic adjustment process. The camera controller 76
When the standby switch 5 is operated, this processing procedure is executed. That is, the camera controller 76 proceeds from step SP1 to step SP2, detects a luminance distribution amount in the luminance signal, and compares the detected luminance distribution amount with the luminance distribution amount held when immediately executing this processing procedure. It is determined whether or not the value has changed by a predetermined value or more. Accordingly, the camera controller 76 determines whether or not the subject has changed to such an extent that the polarization filter 55 needs to be adjusted.

Here, as shown in FIG. 8, the camera controller 76 detects the luminance distribution by dividing the luminance level into two stages based on a predetermined luminance level L. Further, the camera controller 76 counts the number of pixels having a luminance level lower than the luminance level L because the number of pixels of one screen is constant in the imaging result.
The luminance distribution is determined based on the number of pixels distributed at the lower luminance level (the luminance distribution amount at the lower luminance level, which is the area indicated by hatching in FIG. 8). The range below the luminance level L is a range excluding the high luminance level where the change in the luminance level is small with respect to the change in the light amount.

If the number of pixels has not changed by a predetermined value or more, the camera controller 76 proceeds to step SP3 while maintaining the polarization filter 55 at the adjustment position set by executing this processing procedure immediately before and performing this processing. End the procedure. On the other hand, if the number of pixels has changed by a predetermined value or more, a positive result is obtained, and the camera controller 76 stores the amount of luminance distribution based on the number of pixels in the evaluation reference memory.

Subsequently, the camera controller 76 proceeds to step SP4, in which the camera controller 76 controls the operation of the aperture control circuit 78 so as to maintain the current aperture amount, thereby locking the aperture in a state where the luminance distribution amount is detected. I do. Subsequently, the camera controller 76 proceeds to step SP5, and starts rotating the polarization filter 55 in a predetermined direction.

Subsequently, the camera controller 76 proceeds to step SP6, and determines whether or not the rotation of the polarization filter 55 has increased the luminance distribution amount. Here, the camera controller 76 detects the luminance distribution amount in the same manner as in step SP2, and determines whether the luminance distribution amount has increased by comparing the detected luminance distribution amount with the luminance distribution amount detected immediately before in this processing procedure. Judge. Thereby, the camera controller 76 determines whether or not the contrast has increased due to the rotation of the polarizing filter 55.

If a negative result is obtained in step SP6, the camera controller 76 proceeds to step SP7.
The control data is output to the pulse driver 79, and the rotation direction of the polarization filter 55 is reversed.

On the other hand, if a positive result is obtained in step SP6, the camera controller 76 determines in step SP8 whether or not the luminance distribution amount is the maximum.
Here, the camera controller 76 determines in step SP6
It is determined whether or not the luminance distribution amount is the maximum by determining whether or not the luminance distribution amount based on the luminance distribution detected in step 2 is substantially equal to the luminance distribution amount held in the evaluation memory.

If a negative result is obtained here, the camera controller 76 updates the luminance distribution amount held in the evaluation memory to the luminance distribution amount detected in step SP6, and then returns to step SP6.

On the other hand, if a positive result is obtained in step SP8, the process proceeds to step SP9, where the rotation of the polarization filter 55 is stopped. Accordingly, the camera controller 76 repeats the processing procedure of steps SP6-SP8-SP6, and rotates the polarization filter 55 in a direction in which the luminance distribution amount is sequentially increased and the contrast is increased, as indicated by an arrow A in FIG. When the contrast reaches a peak, the rotation procedure is reversed by executing the processing procedure of steps SP6-SP7-SP6, and then the rotation of the polarizing filter 55 is stopped at a point where the luminance distribution amount reaches a peak.

When the camera controller 76 adjusts the polarization filter 55 so that the contrast detected by the luminance distribution is maximized in the state where the aperture is locked in this way, the process proceeds to step SP10, where the lock of the aperture is released. Then, the process proceeds to step SP3 to end this processing procedure.

(1-2) Operation of First Embodiment In the above configuration, in the video camera 1 (FIG. 6), an optical image of a subject is formed on the imaging surface of the CCD solid-state imaging device 50 by the camera lens 2. The image pickup result of the optical image is processed by a sample hold AGC circuit 60, an analog / digital conversion circuit 61, and a camera signal processing circuit 62 to generate a luminance signal and a color difference signal by digital signals.

In the video camera 1, the luminance signal and the chrominance signal are corrected by a camera shake correction circuit 63 and then compressed by an image compression / decompression circuit 64, thereby generating video data to be recorded on the magneto-optical disk 10. You. In the video camera 1, the audio signal obtained by the microphone 69 is processed by the amplifier circuit 70 and the analog-to-digital conversion circuit 71, and then data is compressed by the audio compression / expansion circuit 72, whereby the audio data to be recorded on the magneto-optical disk 10 is obtained. Is generated.

In the video camera 1, the video data and the audio data D1 are supplied to the MD block 11 (FIG. 5), subjected to predetermined signal processing, and subjected to predetermined signal processing.
Thermomagnetic recording. Conversely, the reproduction data obtained from the magneto-optical disk 10 is processed in the reverse order of the recording to reproduce the video data and the audio data D2. It is extended. The audio data is expanded by the audio compression / expansion circuit 72, and the video data and the audio data are output from the liquid crystal display unit 3, the electronic viewfinder 7, and the speaker 75.

At the time of recording and during standby, instead of video data and audio data reproduced from the magneto-optical disk 10, a luminance signal and a color difference signal, which are imaging results output from the image compression / expansion circuit 64, and a sound compression signal are output. The audio signals obtained by the microphone 69 and output from the decompression circuit 72 are respectively supplied to the liquid crystal display unit 3 and the electronic viewfinder 7.
And from the speaker 75. As a result, the subject can be confirmed by the liquid crystal display unit 3 and the electronic viewfinder 7 as needed, and the imaging result of the desired subject can be recorded.

When the standby switch 5 for setting the entire operation mode to a recordable state is operated when the subject is confirmed and recorded in this manner (FIG. 1), the video camera 1 automatically adjusts the aperture. In the state where the aperture is set to the optimal value, the luminance distribution amount distributed in a range excluding the high luminance level, which is less than the luminance level L and whose luminance level change is small with respect to the light amount change, with respect to the luminance signal as the imaging result. Is calculated, and whether or not the subject has changed to such an extent that the polarization filter 55 needs to be adjusted is detected based on the luminance distribution amount.

That is, in the imaging result, if the subject is different, the luminance distribution naturally changes. Even for the same subject, the luminance distribution changes depending on, for example, conditions such as lighting. In the video camera 1, the luminance distribution that changes in this manner is detected by a luminance distribution amount that is the number of pixels equal to or lower than the luminance level L, in two stages based on the luminance level L. That is, a change in the luminance distribution is determined based on the change in the luminance distribution amount.
Adjustment is started.

In this adjustment, with the aperture locked, a luminance distribution is similarly detected based on the amount of luminance distribution, which is the number of pixels below the luminance level L, and the polarization filter 55 is adjusted so that the amount of luminance distribution is maximized. Is rotated.

That is, the polarizing filter is used, for example, to block the light reflected by the glass when the subject is imaged through the glass. Also, for example, when an image of a waterside landscape or the like is taken, it is used so that the dark water bottom is further darkened to increase the overall contrast.

In this case, in the imaging result, the condition that the reflected light is blocked increases, and the lower the water bottom becomes and the higher the contrast becomes, the higher the brightness level becomes, provided that the aperture is locked. Are distributed to the region of low luminance level. That is, the distribution of the luminance level changes to the lower side of the luminance level, and the contrast increases in the imaging result.

As a result, in the video camera 1, the distribution of the luminance filter is set so that the distribution of the luminance level is closest to the side of the lower luminance level and the contrast is maximized.
After adjusting 5, control of the aperture is resumed, and recording of the imaging result is started as necessary. This allows the video camera 1 to automatically adjust the polarization filter.

(1-3) Effects of the First Embodiment According to the above configuration, the luminance level is divided into two levels and the luminance distribution is detected in a state where the aperture is locked, and the contrast in the luminance distribution is detected. By rotating the polarizing filter so that is maximized, the polarizing filter can be automatically adjusted. As a result, the adjustment accuracy can be improved as compared with the case where the imaging result is confirmed and the adjustment is performed manually, so that the polarization filter can be adjusted simply and reliably.

Further, since the polarizing filter can be built in the lens, the diameter of the polarizing filter can be reduced accordingly, and the overall configuration can be reduced accordingly.

By executing the processing procedure of FIG. 1 in conjunction with the operation of the standby switch and adjusting the polarization filter as necessary, it is possible to prevent a user who is unfamiliar with the operation from forgetting the operation.

(2) Other Embodiments In the above-described embodiment, the number of pixels distributed in a range excluding the high luminance level where the change in the luminance level is small with respect to the change in the amount of light is counted to change the luminance distribution. Has been described, and the polarization filter is adjusted by this. However, the present invention is not limited to this, and conversely, the change in the luminance level with respect to the change in the light amount is distributed in a range of a high luminance level. The change in luminance distribution may be detected by counting the number of pixels. In this case, the polarization filter is adjusted so as to minimize the number of pixels.

In the above-described embodiment, the number of pixels distributed in a high luminance level range where the change in the luminance level is small with respect to the change in the light amount with respect to the luminance level L, and the remaining low luminance level range The case where the luminance distribution is detected by classifying the luminance distribution according to the number of pixels to be distributed has been described. However, the present invention is not limited to this, and the luminance level L, which is the boundary, can be variously set as necessary.

Further, in the above-described embodiment, the case has been described where the luminance level is divided into two stages to detect the luminance distribution, and the contrast is determined based on the luminance distribution to adjust the polarization filter. However, the present invention is not limited to this, and the luminance distribution may be detected in two or more stages and the contrast may be determined based on the luminance distribution to adjust the polarization filter. Alternatively, instead of such a division, the luminance distribution may be detected by sampling a specific luminance level, and the contrast may be determined from the luminance distribution to adjust the polarization filter.

In the above embodiment, the case where the aperture is locked and the polarization filter is adjusted has been described. However, the present invention is not limited to this, and the polarization filter may be adjusted with the automatic aperture adjusted. . In this case, the luminance distribution is detected in a range in which the luminance level changes linearly with respect to the change in the light amount, and when the luminance distribution is further detected, the imaging result is sequentially corrected by the aperture of the diaphragm, or It is necessary to sequentially correct the threshold value, which is a criterion for determining the luminance distribution amount, and execute the above-described processing.

In the above embodiment, the case where the polarization filter is automatically adjusted in conjunction with the operation of the standby switch has been described. However, the present invention is not limited to this. The polarization filter may be automatically adjusted by an operation. Further, the luminance distribution may be constantly monitored at regular time intervals, and the luminance distribution may be automatically adjusted when the luminance distribution changes. If you do this,
For example, the deflection filter can be adjusted for an ever-changing subject such as when shooting while panning.

In the above-described embodiment, the case where the polarizing filter is automatically adjusted has been described. However, the present invention is not limited to this. For example, the guide for adjusting the polarizing filter is simply provided by turning on a lamp in an electronic viewfinder. May be formed.

In the above-described embodiment, a case has been described in which the optimum adjustment position of the polarization filter is detected from the imaging result by rotating the polarization filter.
The present invention is not limited to this. For example, the optical path of the incident light is separated on the subject side or the light receiving element side from the polarizing filter, and further, the subject is separately imaged, and the optimum adjustment position of the polarizing filter is detected by a dedicated mechanism. May be. In this way, the present invention can be applied to, for example, a silver halide camera.
In a practically sufficient range, the luminance distribution can be determined using a one-dimensional light receiving element such as a line sensor instead of a two-dimensional image sensor such as a CCD solid-state image sensor.

Further, in the above-described embodiment, the case where the optimum adjustment position of the polarizing filter is detected by rotating the polarizing filter has been described. However, the present invention is not limited to this.
For example, when the optical path of the incident light is separated on the light receiving element side from the polarizing filter, the same as when the polarizing filter is rotated by driving the optical element capable of equalizing control when the polarizing filter is rotated. May be formed in an equalized manner to detect the optimum adjustment position of the polarizing filter.

[0085]

As described above, according to the present invention, the amount of adjustment is determined for a polarizing filter of an optical system that forms an optical image on a light receiving surface based on an image pickup result, so that the polarizing filter can be easily and reliably adjusted. can do.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a processing procedure of a camera controller in a video camera according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the overall configuration of the video camera.

FIG. 3 is a schematic diagram for explaining a magneto-optical disk applied to the video camera of FIG. 2;

FIG. 4 is a table showing a format of the magneto-optical disk of FIG. 3 in comparison with a conventional format.

FIG. 5 is a block diagram showing an MD block of the video camera in FIG. 2;

FIG. 6 is a block diagram illustrating a camera unit of the video camera in FIG. 2;

FIG. 7 is a schematic diagram for explaining a polarizing filter of the camera unit in FIG. 6;

FIG. 8 is a characteristic curve diagram for explaining the processing procedure of FIG. 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Video camera, 2 ... Camera lens, 6 ... Camera part, 10 ... Magneto-optical disk, 55 ... Polarizing filter, 76 ... Camera controller

Claims (14)

[Claims] 1. A light-receiving element for outputting an imaging result of an optical image formed on a light-receiving surface, and a polarizing filter, wherein light transmitted through the polarizing filter is guided to the light-receiving surface to form an optical image on the light-receiving surface. An imaging system, comprising: an optical system that performs the adjustment; and a determination unit that determines an adjustment amount of the polarization filter based on the imaging result. 2. The method according to claim 1, wherein the determination unit detects a luminance distribution on the light receiving surface from the imaging result, and determines an adjustment amount of the polarization filter according to the luminance distribution changed by changing the polarization filter. The imaging device according to claim 1. 3. The imaging apparatus according to claim 1, further comprising a display unit that displays guidance for adjusting the polarization filter based on a determination result of the determination unit. 4. The imaging apparatus according to claim 1, further comprising an adjusting unit that adjusts the polarization filter based on a result of the determination by the determining unit. 5. The imaging apparatus according to claim 4, wherein the adjusting unit adjusts the polarization filter so that a contrast of the optical image is increased when a stop is fixed in the optical system. apparatus. 6. The imaging apparatus according to claim 4, wherein said adjusting means adjusts said polarizing filter when a luminance distribution on said light receiving surface changes by a predetermined value or more. 7. The imaging apparatus according to claim 4, wherein the adjustment unit adjusts the polarization filter in response to an operation of a predetermined operation element. 8. An adjustment of an image pickup apparatus, wherein an adjustment amount is determined for a polarizing filter of an optical system that forms an optical image on the light receiving surface based on an imaging result of an optical image formed on the light receiving surface. Method. 9. The method according to claim 8, wherein a luminance distribution on the light receiving surface is detected from the imaging result, and an adjustment amount of the polarization filter is determined according to the luminance distribution changed by changing the polarization filter. 3. The method for adjusting an imaging device according to claim 1. 10. The method according to claim 8, wherein guidance for adjusting the polarization filter is displayed based on the determination result of the adjustment amount. 11. The method according to claim 8, wherein the polarization filter is adjusted based on a determination result of the adjustment amount. 12. The method according to claim 8, wherein the polarizing filter is adjusted so that the contrast of the optical image is increased when the stop is fixed in the optical system. 13. The method according to claim 8, wherein the polarization filter is adjusted when a luminance distribution on the light receiving surface changes by a predetermined value or more. 14. The method according to claim 8, wherein the polarization filter is adjusted in response to an operation of a predetermined operation element.