GB2029659A - Apparatus and method for electrical processing of picture element information - Google Patents
Apparatus and method for electrical processing of picture element information Download PDFInfo
- Publication number
- GB2029659A GB2029659A GB7922475A GB7922475A GB2029659A GB 2029659 A GB2029659 A GB 2029659A GB 7922475 A GB7922475 A GB 7922475A GB 7922475 A GB7922475 A GB 7922475A GB 2029659 A GB2029659 A GB 2029659A
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- digital
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- signal
- control circuit
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C3/00—Measuring distances in line of sight; Optical rangefinders
- G01C3/32—Measuring distances in line of sight; Optical rangefinders by focusing the object, e.g. on a ground glass screen
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B7/00—Mountings, adjusting means, or light-tight connections, for optical elements
- G02B7/28—Systems for automatic generation of focusing signals
- G02B7/36—Systems for automatic generation of focusing signals using image sharpness techniques, e.g. image processing techniques for generating autofocus signals
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
- G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
- G11B7/0908—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for focusing only
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
- G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
- G11B7/0908—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for focusing only
- G11B7/0917—Focus-error methods other than those covered by G11B7/0909 - G11B7/0916
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Electromagnetism (AREA)
- Optics & Photonics (AREA)
- Automatic Focus Adjustment (AREA)
- Transforming Light Signals Into Electric Signals (AREA)
- Image Analysis (AREA)
- Image Input (AREA)
- Photometry And Measurement Of Optical Pulse Characteristics (AREA)
Abstract
In processing picture element information, analog signals from a number of groups of light detecting elements (11, 12) are compared with a common analog reference signal from a digital to analog converter (15) by a plurality of comparator circuits (17-1 to 17n) which supply write enable signals to a plurality of digital memories (16-1 to 16n) to store digital signals delivered from a control circuit (5), whereby illumination intensity information for each picture element is stored. The stored signals are then read out from the memories, and processed to derive a signal for example for detecting a focal point of cameras or the like optical devices. A slightly different arrangement is described with reference to Figure 3 (not shown). <IMAGE>
Description
SPECIFICATION
Apparatus and method for electrical processing of picture element information
The present invention relates to apparatus and method for electrical processing of picture element information.
More particularly, this invention relates to an apparatus and method for electrically detecting a focal point of cameras or the like optical devices such as a microscope, high density optical recording and reproducing device or the like with the aid of a picture image signal treating circuit.
As a conventional apparatus and method for electrically detecting a focal point of cameras or the like optical devices, it has been proposed to use a light receiving device including a number of light detecting elements, project an optical image whose focal point is to be detected on the light receiving device so as to obtain a picture element information from each of the light detecting elements, and obtain a focal point detecting signal on the basis of such picture element information. In this case, a number of picture element informations are obtained. In order to treat these picture element informations so as to obtain the focal point detecting signal, it is necessary to carry out complex steps. In general, it is preferable to digitally treat the picture element informations.In this case, it is a matter of course that an illumination intensity information obtained from each picture detecting element must be converted into a digital information.
Various kinds of apparatuses and methods for treating the illumination intensity information from a number of picture element informations for the purpose of detecting the focal point of the cameras or the like optical devices have heretofore been proposed. In all of these conventional apparatus and methods, each picture element is scanned by a light image in succession to derive corresponding illumination intensity as an analogue amount which is then converted in succession into a digital amount,
As a result, if the number of the picture elements becomes large, a considerably long time is required for the analog-digital conversion.In orderto eliminate such drawback, if use is made of analog-digital converters which are the same in number as the picture elements for the purpose of simultaneously effecting all of the analog-digital conversions in parallel, a significantly large number of the analogdigital converters are required, thereby making the apparatus complex in construction and making the method troublesome in successive steps.
It is desirable, therefore to provide an apparatus and method for electrically processing picture element information, for instance for detecting a focal point of a camera or the like optical device with the aid of a picture image signal treating circuit including a digital-analog converter and a plurality of comparator circuits for comparing analog signals with each other, which can read out an illumination intensity analog information of each picture element by means of digital signals delivered from a central cc trol circuit, thereby obtaining a signal of detecting a focal point of cameras or the like optical devices.
A feature of the invention is the provision of an apparatus for electrically processing picture element information, for example for detecting a focal point of cameras or the like optical devices with the aid of a picture image signal treating circuit, comprising a light receiving device composed of a number of light detecting elements arranged in a plurality of groups, a selection circuit for selectively operating one of these plurality of groups, a plurality of comparator circuits for comparing output analog signals from the plurality of light detecting elements with a common reference signal, a central control circuit for controlling the plurality of light detecting elements, selection circuits and comparator circuits and generating a digital signal, a digital-analog converter for converting the digital signal generated from the central control circuit into an analog signal and supplying the analog signal as a reference signal to the comparator circuit, and a plurality of digital memories for receiving the output from the comparator circuit as a write enable signal and memorizing the digital signal generated from the central control circuit.
Another feature of the invention is the provision of a method of electrically processing picture element information, for example for detecting a focal point of cameras or the like optical devices, which makes use of a picture image signal treating circuit comprising a number of light detecting elements, a plurality of analog memories for memorizing output signals from the light detecting elements, a digitalanalog converter for converting digital signals delivered from a central control circuit to analog signals, a counter driven by the digital signal delivered from the central control circuit, a plurality of comparator circuits for comparing the output signal delivered from the digital-analog converter and receiving as a reference signal the analog signal memorized in the analog memories, and a plurality of digital memories for memorizing the output digital signals from the central control circuit or the output digital signals from the counter and receiving the output signal from the comparator circuit as a write enable signal, the central control circuit controlling the light detecting elements, analog memories, analog-digital converter, counter, comparator circuits and digital memories and deriving by calculation, for example, an estimation value which is a total sum of contrast values and which can detect a focal point of the optical device from the digital signals stored in the digital memories, and which comprises the successive steps of changing the reference signal in succession by means of the central control circuit so as to search all of the analog signals stored in the analog memories by the reference signal and detect a minimum value of these analog signals, making the minimum value thus detected correspondent with a digital amount of 0 and at the same time making a largest possible value of the analog amount of the analog memories correspondent with a suitably selected positive digital amount, searching all are of the analog memories again so as to introduce the digital amounts corresponding the respective analog amounts into the digital memories corresponding to the respective analog memories, and introducing the digital amount stored in the digital memories into an estimation function given by the estimate values so as to detect a focal point of said optical device.
The invention will be more fully understood from the following exemplary description with reference to the accompanying drawings, in which Figure 1 is a block diagram of one embodiment of an apparatus for electrically detecting a focal point of cameras or the like optical devices with the aid of a picture image signal treating circuit according to the invention;
Figure 2 is a block diagram of one embodiment of the picture image signal treating circuit shown in
Figure 1;
Figure 3 is a block diagram of another embodiment of the picture image signal treating circuit shown in Figure 1;
Figure 4 is a detailed diagrammatic view of an example of the picture image signal treating circuits shown in Figures 2 and 3;
Figure 5 is a detailed diagrammatic view of a digital-analog converter shown in Figure 4; and
Figure 6 is a diagrammatic view of an embodiment of an optical system for the apparatus shown in
Figure 1.
Figure 1 shows one embodiment of an apparatus for electrically detecting a focal point of cameras or the like optical devices with the aid of a picture image signal treating circuit according to the invention. In the present embodiment, an image of an object 1 to be photographed is projected through a photographic optical system 2 onto a light receiving device 3 including a number of light detecting elements, that is, picture element regions. An illumination intensity information of each picture element region of the light receiving device 3 is supplied to a picture image signal treating circuit 4 which functions to convert all of the illumination intensity informations in parallel into digital informations.The digital informations thus obtained are supplied in succession to a central control circuit 5 which functions to suitably treat the digital information so as to obtain a focal point detecting signal which displays the condition that the optical system 2 is in focus. This focal point detecting signal is supplied to a display device 6 which functions to notify a photographer that the optical system 2 is in focus.
The focal point detecting signal is also supplied through an optical system driving circuit 7 to an optical system driving mechanism 8, thereby adjust ing the focal point a" n e optical system 2. in a simple apparatus, the optical system 2 may mannually be driven by the photorapher in response to the indication given by the display device 6 and the driving circuit 7 and driving mechanism 8 may be omitted.
Figure 2 shows bodimentofthe light receiving device ~ ure image signal treating circuit 4 and cent r n@ #;-- r-.': circuit S sha - ir Figure 1 in greater detail. lr h- present embediment, the light receiving device 3 includes a r.u Xber of light detecting elements, that is, picture el -?en.4s divided into two groups 11, 12. These two groups 11,12 are selectively operated through a selection circuit 13 by
means of a central control circuit 5.
If the group 11 of the light detecting elements is selectively operated, illumination intensity informations of n picture elements for constituting the group
11 of the light detecting elements are supplied in parallel to and held by sample hold circuits or analog memories 14-1, 14-2,... 14-n corresponding to respective picture elements. The central control circuit 5 functions to supply digital signals whose values are increased in succession to a digitalanalog converter 15 and digital memorie 16-1, 16-2, ...16-n.
The digital-analog converter 15 serves to convert the digital signals into analog signals which are then supplied to one of the input terminals of comparator circuits 17-1, 17-2,... 17-n, respectively. The other input terminals of the comparator circuits 17-1, 17-2, ...17-n are connected to the output terminals of the sample hold circuits 14-1, 14-2,... 14-n, respectively.
Everytime the digital signals delivered from the central control circuit 5 vary their values, the comparator circuit 17-1, 17-2,... 17-n serves to compare the values of the analog signal held by the sample hold circuit 14-1,14-2,... 14-n and representing the illumination intensity of each picture element for constituting the group 11 of the light detecting elements with the analog signal corresponding to the digital signal delivered from the central control circuit 5. The digital signal delivered from the central control circuit 5 changes from a small value to a large value in succession, so that the analog signal supplied from the digital-analog converter 15 to the comparator circuits 17-1,17-2,... 17-n is also gradually increased.When such gradually increased analog signal exceeds the value of the analog signal held by the sample hold circuit 14-1, 14-2,... 14-2, the output from the comparator circuits 17-1, 17-2,...
17-n becomes reversed. The outputs from the compratorcircuits 17-1,17-2,... 17-n are supplied to digital memories 16-1, 16-2,... 16-n, respectively.
When the outputs from the comparator circuits 17-1, 17-2,... 17-n are reversed, the digital signals supplied from the central control circuit 5 to the digital memories 16-1,16-2... 16-n are memorized in these digital memories.
For example, let the digital signal delivered from the central control circuit 5 be 4 bits and let the output from the comparator circuit 17-2 be reversed when 0011 is delivered from the central control circuit 0011 is memorized in the digital memory i6-2. If the comparator circuit 17-5 is reversed when 0100 is delivered from the central control circuit 5, 3100 is memorized in the digital 16-2. If the compara (or circuit 17-5 is reversed when 0100 is delivered from the central control circuit 5,0100 is memorized in the digital memory 16-5. In this way, during the time at which the digital signal delivered from the central control circuit 5 changes from 0000 to 1111, the illumination intensity signal of each picture element held in the sample hold circuits 14-1, ...
14-n is memorized as the digital signal in the digital memory 16-1, 16-2,... 16-n, respectively. It is a matter of course that if the dynamic range of the analog illumination intensity information of each picture element is wide, it is necessary to effect a logarithmic compression or the like in a suitable manner. Such a role can be played by the digitalanalog converter 15, for example.
As stated hereinbefore, the illumination intensity information of each picture element is memorized in n digital memories 16-1, 16-2,... 16-n corresponding to n picture elements as digital amount at substantially the same time during the time at which the central control circuit 5 supplies comparative digital signals, in the above described embodiment, 0000 to 1111. Subsequently, the central control circuit 5 functions to read out and treat the illumination information of each picture element stored in the digital memories 16-1, 16-2,... 16-n in a suitable manner. It is a matter of course that one of which digital memories 16-1, 16-2,... 16-n is read out, that is, one of which picture element informations is used is determined through an address path 18 and decoder 19 by the central control circuit 5.If the treatment of obtaining a focal point detecting signal with the aid of the group 11 of the light detecting elements is completed in the central control circuit 5, the central control circuit 5 functions to select and treat the group 12 of the light detecting elements by the selection circuit 13 in manner similar to the above, thereby obtaining a focal point detecting signal.
Figure 3 shows another embodiment of the light receiving device 3, picture image signal treating circuit 4 and central control circuit 5 shown in Figure 1 in greater detail. In the present embodiment, the central control circuit 5 functions to supply digital signals whose values are increased in succession to a digital-analog converter 15, digital memories 16-1, 16-2,... 16-n and 16'-1, 16'-2... 16'-n and address decode circuit 19 connected to the digital memories 16'-1, 16'-2 ... 16'-n. Provision is made of a 6 bits counter 20 driven by the central control circuit 5.
Preceding 4 bits output signal from the converter 20 is supplied to the digital memories 16-1, 16-2,... 16-n and the succeeding 2 bits output signal from the counter 20 is supplied to the digital memories 16'-1, 16'-2 ... 16'-n. The outputfrom the digital memories 16'-1, 16'-2 16'-n consists of 4 bits. This is because of the fact that when the group 12 of light detecting elements are selected after the group 11 of light detecting elements has been selected, the succeeding 2 bits are added to the succeeding 2 bits of the group 11 of light detecting elements and are handled as the 4 bits.
All of the analog signals stored in the sample hold circuits 14-1, 14-2,... 14-n are searched by supplying digital signals in succession from the central control circuit 5 to the digital-analog converter 15 so as to detect the minimum value from these analog signals stored in the sample hold circuits 14-1, 14-2,... 14-n.
The count signal of the counter 20 is set to O in correspondence with the digital signal supplied to the digital analog converter 15 and corresponding to the minimum value thus detected in the sample hold circuits 14-1, 14-2,... 14-n. At the same time, the largest possible maximum value of the analog amount in the sample hold circuits 14-1, 14-2,... 14-n is made correspondent with the suitably selected positive digital amount. Then, the sample hold circuits 14-1, 14-2,... 14-n are searched again in the same manner as in the above case so as to introduce the output digital signals from the counter 20 corresponding to the above analog amount into the digital memories 16-1,16-2,... 16-n and 16-1, 16'-2, 16'-n, respectively.That is, the digital signals delivered from the central control circuit 5 change their values in succession from small values to large values. As a result, the analog signal supplied from the digital-analog converter 15 to the comparator circuits 17-1, 17-2,... 17-n is also gradually increased.
If this analog signal exceeds the analog signals held in the sample hold circuits 14-1, 2, 14-2,... 14-n, the outputs from the corresponding comparator circuits 17-1, 17-2,... 17-n become reversed. The outputs from the comparator circuits 17-1, 17-2,... 17-n are supplied to the digital memories 16-1,16-2,... 16-n and 16'-1, 16'-2, ... 16'-n, respectively, such that if the outputs from the comparator circuits 17-1, 17-2,...
17-n are reversed, the counter signals from the counter 20 are memorized in the digital memories 16-1,16-2,... 16-n and 16'-1,16'-2,... 16'-n. Then, the central control circuit 5 functions to drive the address decode circuit 19 so as to read out the 4 bits picture element information stored in the digital memories 16-1, 16-2,... 16-n, thereby detecting the focal point according to the predetermined estimation function of an estimate value which is the total sum of contrast of the picture elements.
If the 4 bits picture element information stored in the digital memories 16-1, 16-2,... 16-n is not sufficient enough to detect the focal point, the 2 bits picture element information stored in the digital memories 1 6'-1, 16'-2,... 1 6'n is also read out. These 2 bits picture element information is added to the 4 bits picture element information to obtain a 6 bits picture image information which is sufficient to detect the condition under which the optical system 2 is in focus according to the predetermined estimation function. Similarly, it is possible to detect the condition under which the optical system 2 is in focus with respect to the group 12 of light detecting elements.Thus, the optical system 2 can be brought into in focus by comparing the focus point of the optical system 2 with respect to the group 11 of light detecting elements with that with respect to the group 12 of light detecting elements.
Figure 4 shows in detail an example Df the picture image signal treating circuit shown in Figures 2 and 3. In the present example, the light receiving element 3 is divided into two groups 11-n, 1 1-n-1,... 11-1 and 12-n, 12-n-1,... 12-1 and each light receiving element is composed of a condenser and light receiving diode. The selection circuit 13 is divided into a plurality of switches 13-n, 13-n-I, ...13-1. Each selection circuit is made inoperative by a signal supplied from a central pressing unit (cpu). Each of the plurality of sample hold circuits 14-n, 14-n-1,... 14-1 is composed of a condenser and an electronic switch. Each of the plurality of comparator circuits 17-n, 17-n-1,... 17-1 is composed of a differential amplifier. The digital-analog converter is shown in greater detail in Figure 5. As the counter 20 shown in
Figure 3, use may be made of a circuit type So54192 synchronous 4-bit up/down counter (dual clock with clear) of Texas Instruments Incorporated. As the address decode circuit 19, use may be made of a circuit type SN54154 544-line-to-i 6-line decoder/de- multiplexer of Texas Instruments Incorporated. As the digital memory 16, use may be made of
MC14508B dual 4-bit latch constructed with MOS
P-channel and N-channel enhancement mode devices in a single monolithic structure.
Figure 6 shows an embodiment of an optical system for an apparatus for electrically detecting a focal point of cameras or the like optical devices with the aid of a picture image signal treating circuit according to the invention. In the present embodiment, adjacent to a predetermined focal plane 21 are arranged two groups 11, 12 of light detecting elements side by side and in front of the group 12 of light detecting elements is arranged a transparent plate 24 for adjusting the light path length. A focal point detecting light is incident through an optical system 2 and mirror 25 on the groups 11, 12 of light detecting elements. If the mirorr 25 is minutely oscillated, the focal point detecting light is also oscillated to project the same portion of the light image onto the groups 11, 12 of light detecting elements in an alternate manner.In front of the group 12 of light detecting element is arranged the transparent plate 24, so that the position of the light receiving surface of the group 12 of light detecting element is equivalent to the position in the rear of the predetermined focal plane 21. As a result, if the groups 11, 12 of light detecting elements are changed over by the selection circuit 13 so as to use either one of these groups, it is possible to obtain the same effect as in the case of detecting the focal point in front and rear of the predetermined focal plane 21.
Thus, the direction of displacement of the focal point can also be detected. The light detecting elements in the groups 11, may be arranged in longitudinal and transverse directions so as to form a grid or may be concentrically arranged.
The invention is not limited to the above described embodiments and various alternations and changes are possible. For example, the apparatus and method according to the invention are not limited to the use of detecting the focal point, but may be used for other picture image treatments in which a number of picture element informations must be digitally treated at a high speed. In the above described embodiment shown in Figure 2, the informations stored in the digital memories 16-1, 16-2,... 16-n are supplied to the central control circuits and after the treatment has been completed the groups of the light detecting elements are changed over one from the other. The illumination intensity information of the group of the light detecting elements thus changed over is stored in the digital memories 16-1, 16-2,... 16-n.Alternatively, all of the illumination intensity information of the two groups of the light detecting elements may be stored in the digital memories 16-1, 16-2,... 16-n, and treated in association with each other.
The invention is capable of changing a number of picture element informations into digital informations at a high speed. As a result, when the invention is applied to the focal point detection, for example, a focal point of a movable object to be photographed can be detected. In addition, in the case of changing a number of picture element informations into digital informations at a high speed, use may be made of only one digital-analog converter.
In the embodiment shown in Figures 2 and 3, the analog informaton of all of the picture elements are treated in parallel, so that the treating speed is faster than that of the series reading out treatment. In addition, the use of the analog information produced at the same instant provides the important advan tagethatthefocal point can be detected in a more accurate manner.
Claims (6)
1. An apparatus for electrically processing picture element information with the aid of a picture image signal treating circuit, comprising a light receiving device composed of a number of light detecting elements arranged in a plurality of groups, a plurality of selection circuits for selectively operating one of said plurality of groups, a plurality of comparator circuits for comparing output analog signals from said number of light detecting elements with a common reference signal, a central control circuit for controlling said number of light detecting elements, selection circuits and comparator circuits so as to generate a digital signal, a digital-analog converter for converting said digital signal generated from said central control circuit into an analog signal and supplying said analog signal as said reference signal to said comparator circuit, and a plurality of digital memories for receiving the output from said comparator circuit as a write enable signal and memorizing said digital signal generated from said central control circuit.
2. The apparatus according to claim 1 and comprising further a plurality of sample hold circuits connected between said number of light detecting elements and said plurality of comparator circuits and holding the outputfrom said number of light detecting elements, said plurality of comparator circuits comparing the sample holding signals from said plurality of sample hold circuits with said common reference signal.
3. Apparatus as claimed in claim 1 or 2, for detecting a focal point of an optical device arranged to deliver a picture image to the light receiving device.
4. A method of electrically processing picture element information for detecting a focal point of an optical device, which makes use of a picture image signal treating circuit comprising a number of light detecting elements, a plurality of analog memories for memorizing output signals from said light detecting elements, a digital-analog converterforconverting digital signals delivered from a central control circuit to analog signals, a counter driven by the digital signal delivered from said central control circuit, a plurality of comparation circuits for comparing the output signal delivered from said digitalanalog converter and serving as a reference signal with the analog signal memorized in said analog memories, and a plurality of digital memories for memorizing the output digital signals from said central control circuit or the output digital signals from said counter and receiving the output signal from said comparator circuit as a write enable signal, said central control circuit controlling said light detecting elements, analog memories, analog-digital converter, counter, comparator circuits and digital memories and deriving by calculation an estimation value which can detect a focal point of said optical device from the digital signals stored in said digital memories, and which comprises the successive steps of changing said reference signal in succession by means of said central control circuit so as to search all of the analog signals stored in said analog memories by said reference signal and detect a minimum value of said analog signals, making said minimum value thus detected correspondent with a digital amount of 0 and at the same time making a largest possible value of the analog amount of said analog memories correspondent with a suitably selected positive digital amount, searching all of said analog memories again so as to introduce said digital amounts corresponding to respective analog amounts into said digital memories corresponding to said respective analog memories, and introducing the digital amount stored in said digital memories into a given estimation function so as to detect a focal point of said optical device.
5. Apparatus for processing picture element information substantially as hereinbefore described with reference to Figure 1, Figures 1 and 2, Figures 1 and 3, Figures 1 and 4, Figures 1,4 and 5, or Figures 1 and 6 of the accompanying drawings.
6. A method of processing picture element information substantially as hereinbefore described with reference to Figure 1, Figures 1 and 2, Figures 1 and 3, Figures 1 and 4, Figures 1,4 and 5 or Figures 1 and 6 of the accompanying drawings.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7974178A JPS558102A (en) | 1978-07-03 | 1978-07-03 | Picture signal process circuit |
| JP12719078A JPS5553304A (en) | 1978-10-16 | 1978-10-16 | Focus detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2029659A true GB2029659A (en) | 1980-03-19 |
| GB2029659B GB2029659B (en) | 1982-09-29 |
Family
ID=26420739
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7922475A Expired GB2029659B (en) | 1978-07-03 | 1979-06-28 | Apparatus and method for electrical processing of picture element information |
Country Status (3)
| Country | Link |
|---|---|
| DE (1) | DE2926898C2 (en) |
| FR (1) | FR2431680A1 (en) |
| GB (1) | GB2029659B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2581157B1 (en) * | 1985-04-29 | 1987-05-29 | Legris Sa | IMPROVEMENT IN THE DISTRIBUTION OF FLUIDS IN MULTIPLE CONDUITS. |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3967056A (en) * | 1973-02-26 | 1976-06-29 | Minolta Camera Kabushiki Kaisha | Automatic focusing apparatus |
| US4047187A (en) * | 1974-04-01 | 1977-09-06 | Canon Kabushiki Kaisha | System for exposure measurement and/or focus detection by means of image senser |
| JPS5156627A (en) * | 1974-11-13 | 1976-05-18 | Canon Kk | Butsutaizosenmeidokenshutsuhoshiki |
-
1979
- 1979-06-28 GB GB7922475A patent/GB2029659B/en not_active Expired
- 1979-07-02 FR FR7917155A patent/FR2431680A1/en active Granted
- 1979-07-03 DE DE19792926898 patent/DE2926898C2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| FR2431680B1 (en) | 1985-05-17 |
| DE2926898A1 (en) | 1980-01-24 |
| DE2926898C2 (en) | 1982-07-22 |
| GB2029659B (en) | 1982-09-29 |
| FR2431680A1 (en) | 1980-02-15 |
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