Patent EP0393401A2 successfully refreshed from Google Patents.
EP0393401A2
Expired / Lapsed
EP
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Image pickup apparatus, as well as method and system for exposure control thereof
Assignee: Hitachi Ltd
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Filing: 1990-03-29
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Granted: —
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Expires: 2010-03-29
Abstract
Abstract Disclosed are an image pickup apparatus and method and system for controlling the exposure of the image pickup apparatus. The image pickup apparatus includes a circuit (12) for detecting a voltage corresponding to a current value of an iris, a circuit (15, 16) for generating a voltage corresponding to a desired iris value, a circuit (18) for comparing the two voltages, and a circuit (7) for controlling the iris based on the result of the comaprison so as to keep the iris value at the desired value, in which the exposure start time of an image pickup device (1) is changed in an increment/decrement of one horizontal scanning period and/or in an increment/decrement of a period shorter than one horizontal scanning period to thereby make it possible to perform manual-iris mode automatic exposure control.
Inventors
- 👤 Takuya Imaide
- 👤 Toshiro Kinugasa
- 👤 Naoki Yamamoto
- 👤 Tomoyuki Kurashige
- 👤 Hiroyuki Tarumizu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 13:14
CPC Classifications
G; G03; G03B; G03B7/00; H; H04; H04N; H04N23/00; H04N23/70; H04N23/72
Claims Analysis
Total Claims: 45
Claim 1
Independent Claim
66 words
An exposure control method in an image pickup apparatus comprising the steps of: generating a desired iris value; detecting a current iris value of an iris of said image pickup apparatus; comparing said current iris value with said desired iris value; and controlling said iris based on the result of the comparison to thereby keep the iris value to be substantially equal to said desired value.
Claim 2
Dependent Claim
66 words
An exposure control method in an image pickup apparatus comprising the steps of: generating a desired iris value; detecting a current iris value of an iris of said image pickup apparatus; comparing said current iris value with said desired iris value; and controlling said iris based on the result of the comparison to thereby keep the iris value to be substantially equal to said desired value.
Claim 3
Dependent Claim
86 words
An exposure control method in an image pickup apparatus comprising the steps of: determining whether the quantity of light for exposure is within a proper range or not; and changing the exposure start time of said image pickup apparatus in an increment/decrement of one horizontal scanning period and/or changing the exposure end time of the same in an increment/decrement shorter than one horizontal scanning period when the quantity of light is out of said proper range, and then returning the control to the aforementioned judgment step.
Claim 4
Dependent Claim
86 words
An exposure control method in an image pickup apparatus comprising the steps of: determining whether the quantity of light for exposure is within a proper range or not; and changing the exposure start time of said image pickup apparatus in an increment/decrement of one horizontal scanning period and/or changing the exposure end time of the same in an increment/decrement shorter than one horizontal scanning period when the quantity of light is out of said proper range, and then returning the control to the aforementioned judgment step.
Claim 5
Dependent Claim
66 words
An exposure control method in an image pickup apparatus comprising the steps of: controlling an iris while limiting the iris value of said iris so as not to exceed a predetermined value; and controlling the level of an output signal of an image pickup device by automatically adjusting (a) an exposure period of time and/or (b) the gain of an amplifier for amplifying said output signal.
Claim 6
Dependent Claim
66 words
An exposure control method in an image pickup apparatus comprising the steps of: controlling an iris while limiting the iris value of said iris so as not to exceed a predetermined value; and controlling the level of an output signal of an image pickup device by automatically adjusting (a) an exposure period of time and/or (b) the gain of an amplifier for amplifying said output signal.
Claim 7
Dependent Claim
60 words
An exposure control method according to Claim 3, in which said iris controlling step includes steps of: generating a desired iris value; detecting a current iris value; comparing said current value with said desired iris value; changing said iris based on the result of the comparison; and limiting said desired iris value so as not to exceed said predetermined value.
Claim 8
Dependent Claim
80 words
An exposure control method in an image pickup apparatus comprising the steps of: controlling an iris of said image pickup apparatus; and controlling an exposure period of time, wherein said iris controlling step includes the steps of: generating a desired iris value; detecting a current iris value of said iris; comparing said current iris value with said desired iris value; and controlling said iris based on the result of the comparison to keep the iris value at said desired value.
Claim 9
Dependent Claim
80 words
An exposure control method in an image pickup apparatus comprising the steps of: controlling an iris of said image pickup apparatus; and controlling an exposure period of time, wherein said iris controlling step includes the steps of: generating a desired iris value; detecting a current iris value of said iris; comparing said current iris value with said desired iris value; and controlling said iris based on the result of the comparison to keep the iris value at said desired value.
Claim 10
Dependent Claim
74 words
An exposure control method according to Claim 5, in which said exposure period of time controlling step includes the steps of: comparing the level of an output signal of an image pickup device of said image pickup apparatus with the level of a reference signal; and changing said exposure period of time based on the result of said comparison so as to make an error as the result of said comparison be substantially zero.
Claim 11
Dependent Claim
57 words
An exposure control method according to Claim 6, in which said exposure period of time changing step includes the step of changing the exposure start time of said image pickup apparatus in an increment/decrement of one horizontal scanning period and changing the exposure end time of the same in an increment/decrement shorter than one horizontal scanning period.
Claim 12
Dependent Claim
69 words
An exposure control method according to Claim 6, further comprising the step of amplifying the output of said image pickup device with a variable gain so as to obtain a predetermined output level of said image pickup device, said exposure period of time changing step including the step of changing the exposure period of time of said image pickup device substantially in an increment/decrement of one horizontal scanning period.
Claim 13
Dependent Claim
31 words
An exposure control method according to Claim 5, further comprising the step of controlling said iris so as to set said iris value not to be larger than a predetermined value.
Claim 14
Dependent Claim
36 words
An exposure control method according to Claim 5, further comprising the step of controlling said exposure period of time so as to set said exposure period of time not to be shorter than a predetermined value.
Claim 15
Dependent Claim
101 words
An automatic exposure control method in an image pickup apparatus comprising the steps of: setting the relationship between an exposure period of time and an iris value of an iris with respect to each of various values of illumination intensity in advance; selecting an exposure period of time and an iris value corresponding to a signal output of an image pickup device; controlling said image pickup device and said iris based on said selected exposure period of time and said selected iris value; and limiting said iris so that the iris value of said iris does not exceed a predetermined time.
Claim 16
Dependent Claim
101 words
An automatic exposure control method in an image pickup apparatus comprising the steps of: setting the relationship between an exposure period of time and an iris value of an iris with respect to each of various values of illumination intensity in advance; selecting an exposure period of time and an iris value corresponding to a signal output of an image pickup device; controlling said image pickup device and said iris based on said selected exposure period of time and said selected iris value; and limiting said iris so that the iris value of said iris does not exceed a predetermined time.
Claim 17
Dependent Claim
39 words
An automatic exposure control method according to Claim 11, in which said iris controlling step is followed by the step of controlling the exposure start time of said image pickup device in an increment/decrement of one horizontal scanning period.
Claim 18
Dependent Claim
176 words
An image pickup apparatus comprising: a lens and an iris (8); means (7) for driving said iris; means (2, 4, 5, 7, 16, 17, 12, 30) connected to said drive means, for controlling said iris automatically; means (2, 4, 5, 7, 16, 17, 12, 30) connected to said drive means and for controlling said iris manually; an image pickup device (1); means (22) connected to said image pickup device, for driving said image pickup device to control the exposure period of time of said image pickup device; means (2, 4, 17, 21, 30, 22) connected to said image pickup device drive means, for controlling the exposure period of time automatically; means (2, 4, 17, 21, 30, 22) connected to said image pickup device drive means, for controlling the exposure period of time manually; means (29; 102) for selecting one of said automatic iris control means and said manual iris control means; and means (29; 103) for selecting one of said automatic exposure period of time control means and said manual exposure period of time control means.
Claim 19
Dependent Claim
176 words
An image pickup apparatus comprising: a lens and an iris (8); means (7) for driving said iris; means (2, 4, 5, 7, 16, 17, 12, 30) connected to said drive means, for controlling said iris automatically; means (2, 4, 5, 7, 16, 17, 12, 30) connected to said drive means and for controlling said iris manually; an image pickup device (1); means (22) connected to said image pickup device, for driving said image pickup device to control the exposure period of time of said image pickup device; means (2, 4, 17, 21, 30, 22) connected to said image pickup device drive means, for controlling the exposure period of time automatically; means (2, 4, 17, 21, 30, 22) connected to said image pickup device drive means, for controlling the exposure period of time manually; means (29; 102) for selecting one of said automatic iris control means and said manual iris control means; and means (29; 103) for selecting one of said automatic exposure period of time control means and said manual exposure period of time control means.
Claim 20
Dependent Claim
108 words
An image pickup apparatus comprising: a lens and an iris (8); means (7) for driving said iris; an image pickup device (1); means (11, 22) for driving said image pickup device; means (12) for generating a signal corresponding to a current iris value; means (15, 16; 16, 19, 20) for generating a signal corresponding to a desired iris value; and means (18) for comparing said signal corresponding to said current iris value with said signal corresponding to said desired iris value to thereby control said iris driving means based on the result of the comparison to keep the iris value of said iris at said desired iris value.
Claim 21
Dependent Claim
108 words
An image pickup apparatus comprising: a lens and an iris (8); means (7) for driving said iris; an image pickup device (1); means (11, 22) for driving said image pickup device; means (12) for generating a signal corresponding to a current iris value; means (15, 16; 16, 19, 20) for generating a signal corresponding to a desired iris value; and means (18) for comparing said signal corresponding to said current iris value with said signal corresponding to said desired iris value to thereby control said iris driving means based on the result of the comparison to keep the iris value of said iris at said desired iris value.
Claim 22
Dependent Claim
103 words
An image pickup apparatus according to Claim 14, further comprising: second comparison means (17) for comparing the level of the output signal of said image pickup device with the level of a reference signal; and an exposure period of time changing means (21) connected to said drive means, for changing the exposure start time of said image pickup device in an increment/decrement of one horizontal scanning period based on the output of said second comaprison means to thereby adjust the level of the output signal of said image pickup device so as to be substantially equal to the level of said reference signal.
Claim 23
Dependent Claim
42 words
An image pickup apparatus according to Claim 15, further comprising means (21, 25) for changing the exposure end time of said image pickup device in an increment/decrement of a period shorter than one horizontal scanning period based on said second comparison means.
Claim 24
Dependent Claim
35 words
An image pickup apparatus according to Claim 15, further comprising a variable gain amplifier means (28) connected to receive the output signal of said image pickup device, for operating to keep the output substantially constant.
Claim 25
Dependent Claim
88 words
An image pickup apparatus according to Claim 14, further comprising: an iris value limiting means (31) connected to said desired iris value generating means, for limiting said current iris value so as not to exceed a predetermined value; and control means (2, 4, 5, 16, 17, 21) connected to said drive means (31), for controlling said drive means in response to the operation of said iris value limiting means so as to keep the level of the output signal of said image pickup device at a predetermined value.
Claim 26
Dependent Claim
84 words
An image pickup apparatus according to Claim 18, wherein said drive control means including: means (4) for detecting the output signal of said image pickup means; means (17) for comparing the level of the detection signal with the level of a reference signal (5); and drive control means (21) for controlling said image pickup device driving means based on the result of the comparison, said drive control means including means for changing the exposure period of time based on the result of the comparison.
Claim 27
Dependent Claim
114 words
An image pickup apparatus comprising: a lens and an iris (8); means (7) for driving said iris; first control means (2, 4, 12, 16-18) connected to said iris drive means, for controlling said iris drive means to limit said iris manually or automatically; an image pickup device (1); means (22) for driving said image pickup device; second control means (2, 4, 17, 21, 22) connected to said image pickup device drive means, for controlling said image pickup device drive means to limit the exposure period of time manually or automatically; and means (31) connected to said first and second control means, for limiting the iris value so as not to exceed a predetermined value.
Claim 28
Dependent Claim
114 words
An image pickup apparatus comprising: a lens and an iris (8); means (7) for driving said iris; first control means (2, 4, 12, 16-18) connected to said iris drive means, for controlling said iris drive means to limit said iris manually or automatically; an image pickup device (1); means (22) for driving said image pickup device; second control means (2, 4, 17, 21, 22) connected to said image pickup device drive means, for controlling said image pickup device drive means to limit the exposure period of time manually or automatically; and means (31) connected to said first and second control means, for limiting the iris value so as not to exceed a predetermined value.
Claim 29
Dependent Claim
113 words
An image pickup apparatus comprising: a lens and an iris (8); an iris control means (2, 4, 17, 16, 12) for controlling said iris; an image pickup device (1); means (22) for driving said image pickup device; exposure period of time control means (21, 29, 30) connected to said image pickup device drive means, for controlling the exposure period of time manually or automatically; and means (32) connected to both said iris control means and said exposure period of time control means, for limiting the iris value so as not to exceed a predetermined value and for limiting the exposure period of time so as not to be shorter than a prdetermined value.
Claim 30
Dependent Claim
113 words
An image pickup apparatus comprising: a lens and an iris (8); an iris control means (2, 4, 17, 16, 12) for controlling said iris; an image pickup device (1); means (22) for driving said image pickup device; exposure period of time control means (21, 29, 30) connected to said image pickup device drive means, for controlling the exposure period of time manually or automatically; and means (32) connected to both said iris control means and said exposure period of time control means, for limiting the iris value so as not to exceed a predetermined value and for limiting the exposure period of time so as not to be shorter than a prdetermined value.
Claim 31
Dependent Claim
29 words
An image pickup apparatus according to Claim 21, in which said iris control means includes means (12, 16, 29, 30) for setting said iris to a desired iris value.
Claim 32
Dependent Claim
192 words
An exposure control system for use in an image pickup apparatus, said system comprising: an iris (201; 301; 401); means (203, 204; 303, 304; 403, 404) for generating an iris value signal corresponding to the iris value of said iris; conversion means (221; 321; 421) for converting the iris value signal into a digital signal; storage means (220; 320; 420) for storing a given train of numerical values having the same number of digits as the quantization number of said conversion means; memory means (225; 325; 425) for memorizing one or more numerical values substantially equal to any one of values which can be taken by the digital value of said iris value signal; means (216, 225; 316, 325; 416, 425) for selecting any one of said one or more numerical values memorized in said memory means so as to make said storage means to store said selected one numerical value into said storage means; and control means (222-224, 202; 322-324, 302; 422-424, 402) for controlling said iris so that the numerical value stored in said storage means and the digital value obtained by said conversion means are substantially coincident witheach other.
Claim 33
Dependent Claim
192 words
An exposure control system for use in an image pickup apparatus, said system comprising: an iris (201; 301; 401); means (203, 204; 303, 304; 403, 404) for generating an iris value signal corresponding to the iris value of said iris; conversion means (221; 321; 421) for converting the iris value signal into a digital signal; storage means (220; 320; 420) for storing a given train of numerical values having the same number of digits as the quantization number of said conversion means; memory means (225; 325; 425) for memorizing one or more numerical values substantially equal to any one of values which can be taken by the digital value of said iris value signal; means (216, 225; 316, 325; 416, 425) for selecting any one of said one or more numerical values memorized in said memory means so as to make said storage means to store said selected one numerical value into said storage means; and control means (222-224, 202; 322-324, 302; 422-424, 402) for controlling said iris so that the numerical value stored in said storage means and the digital value obtained by said conversion means are substantially coincident witheach other.
Claim 34
Dependent Claim
119 words
An exposure control system according to Claim 23, further comrising: means (307) for generating a signal representing a quantity of exposure light; means (310) for generating a reference signal representing a reference quantity of exposure light; and means (309) for comparing said signal representing said quantity of exposure light with said reference signal; wherein said storage means includes an up-down counter (320) having an input terminal connected to the output of said comparison means, said up-down counter being responsive to an externally applied signal (316) so as to put out, as the numerical value stored in said storage means, a numerical value which is increased or decreased in accordance with the result of the comaprison in said comparison means.
Claim 35
Dependent Claim
36 words
An exposure control system according to Claim 24, in which the numerical value which can be taken by said up-down counter is limited so that said iris is prevented from being reduced beyond a predetermined value.
Claim 36
Dependent Claim
57 words
An exposure control system according to Claim 24, said control means including means for generating a pulse having a duty factor which changes in accordance with a difference or ratio between the numerical value put out from said up-down counter and the digital value obtained by said conversion means, said iris being controlled based on said pulse.
Claim 37
Dependent Claim
196 words
An exposure control system for use in an image pickup apparatus, said system comprising: an iris (201; 301; 401); means (203, 204; 303, 304; 403, 404) for generating a signal corresponding to the iris value of said iris; means (225; 325; 425) for generating one or more signals corresponding to a single target iris value or a plurality of target iris values any one of which can be externally selected; means (210; 310; 410) for generating a signal corresponding to a quantity of exposure light; means (220, 222, 223, 224; 320, 322, 323, 324; 420, 422, 423, 424) for generating a signal corresponding to a reference quantity of exposure light; and an iris control means for controlling said iris, said iris control means including means for changing the operation speed of said iris in accordance with one or more factors selected from (a) a difference or a ratio between the current quantity of exposure light and the reference quantity of exposure light (227, 228, 229 in Fig. 34), (b) a difference or a ratio between the current iris value and the target iris value (Fig. 38), and (c) the current iris value (427 in Fig. 4).
Claim 38
Dependent Claim
196 words
An exposure control system for use in an image pickup apparatus, said system comprising: an iris (201; 301; 401); means (203, 204; 303, 304; 403, 404) for generating a signal corresponding to the iris value of said iris; means (225; 325; 425) for generating one or more signals corresponding to a single target iris value or a plurality of target iris values any one of which can be externally selected; means (210; 310; 410) for generating a signal corresponding to a quantity of exposure light; means (220, 222, 223, 224; 320, 322, 323, 324; 420, 422, 423, 424) for generating a signal corresponding to a reference quantity of exposure light; and an iris control means for controlling said iris, said iris control means including means for changing the operation speed of said iris in accordance with one or more factors selected from (a) a difference or a ratio between the current quantity of exposure light and the reference quantity of exposure light (227, 228, 229 in Fig. 34), (b) a difference or a ratio between the current iris value and the target iris value (Fig. 38), and (c) the current iris value (427 in Fig. 4).
Claim 39
Dependent Claim
221 words
An image pickup apparatus comprising: an image pickup device (305); an iris (301); first signal generation means (301-304) for generating an iris value signal representing the iris value of said iris; means (321) for converting said signal representing the iris value into a digital value; second signal generation means (307) for generating a signal representing a quantity of exposure light; drive means (306) for driving said image pickup device to control the exposure period of time of said image pickup device; exposure period of time control means (308-310, 319, 326) for controlling said drive means based on the output of said second signal generation means so as to keep the quantity of exposure light at a predetermined value; memory means (325) for memorizing one or more numerical values substantially equal to any one of values which can be taken by the digital value of said iris value signal; means (316, 325) for selecting any one of said one or more numerical values memorized in said memory means so as to make said storage means to store said selected one numerical value into said storage means; and control means (322, 323, 324, 302) for controlling said iris so that the numerical value stored in said storage means and the digital value obtained by said conversion means are substantially coincident with each other.
Claim 40
Dependent Claim
221 words
An image pickup apparatus comprising: an image pickup device (305); an iris (301); first signal generation means (301-304) for generating an iris value signal representing the iris value of said iris; means (321) for converting said signal representing the iris value into a digital value; second signal generation means (307) for generating a signal representing a quantity of exposure light; drive means (306) for driving said image pickup device to control the exposure period of time of said image pickup device; exposure period of time control means (308-310, 319, 326) for controlling said drive means based on the output of said second signal generation means so as to keep the quantity of exposure light at a predetermined value; memory means (325) for memorizing one or more numerical values substantially equal to any one of values which can be taken by the digital value of said iris value signal; means (316, 325) for selecting any one of said one or more numerical values memorized in said memory means so as to make said storage means to store said selected one numerical value into said storage means; and control means (322, 323, 324, 302) for controlling said iris so that the numerical value stored in said storage means and the digital value obtained by said conversion means are substantially coincident with each other.
Claim 41
Dependent Claim
108 words
An image pickup apparatus according to Claim 28, further comprising: means (310) for generating a reference signal representing a reference quantity of exposure light; and means (309) for comparing said signal representing the quantity of exposure light with said reference signal; and wherein said storage means includes an up-down counter (320) having an input terminal connected to the output of said comparison means, said up-down counter being responsive to an externally applied signal (316) so as to put out, as the numerical value stored in said storage means, a numerical value which is incremented or decremented in accordance with the result of an comparison in said comparison means.
Claim 42
Dependent Claim
36 words
An image pickup apparatus according to Claim 29, in which the nuemrical value which can be taken by said up-down counter is limited so that said iris is prevented from being reduced beyond a predetermined value.
Claim 43
Dependent Claim
57 words
An image pickup apparatus according to Claim 29, said control means including means for generating a pulse having a duty factor which changes in accordance with a difference or ratio between the numerical value put out from said up-down counter and the digital value obtained by said conversion means, said iris being controlled based on said pulse.
Claim 44
Dependent Claim
240 words
An image pickup apparatus comprising: an image pickup device (205; 305; 405); an iris (201; 301; 401); means (202-204; 302-304; 402-404) for generating a signal representing the iris value of said iris; means (207; 307; 407) for generating a signal representing a quantity of exposure light; drive means (206; 306; 406) for driving said image pickup devide to control the exposure period of time said image pickup device; an exposure period of time control means (208-210, 219, 226; 308-310, 319, 326; 408-410, 419, 426) for controlling said drive means based on the output of said second signal generation means so as to keep the quantity of exposure light at a predetermined value; means (225; 325; 425) for generating one or more signals corresponding to a single target iris value or a plurality of target iris values any one of which can be externally selected; means (210; 310; 410) for generating a signal corresponding to a reference quantity of exposure light; and an iris control means for controlling said iris, said iris control means including means for changing the operation speed of said iris in accordance with one or more factors selected from (a) a difference or a ratio between the current quantity of exposure light and the reference quantity of exposure light (227, 228, 229), (b) a difference or a ratio between the current iris value and the target iris value (Fig. 38), and (c) the current iris value (427).
Claim 45
Dependent Claim
240 words
An image pickup apparatus comprising: an image pickup device (205; 305; 405); an iris (201; 301; 401); means (202-204; 302-304; 402-404) for generating a signal representing the iris value of said iris; means (207; 307; 407) for generating a signal representing a quantity of exposure light; drive means (206; 306; 406) for driving said image pickup devide to control the exposure period of time said image pickup device; an exposure period of time control means (208-210, 219, 226; 308-310, 319, 326; 408-410, 419, 426) for controlling said drive means based on the output of said second signal generation means so as to keep the quantity of exposure light at a predetermined value; means (225; 325; 425) for generating one or more signals corresponding to a single target iris value or a plurality of target iris values any one of which can be externally selected; means (210; 310; 410) for generating a signal corresponding to a reference quantity of exposure light; and an iris control means for controlling said iris, said iris control means including means for changing the operation speed of said iris in accordance with one or more factors selected from (a) a difference or a ratio between the current quantity of exposure light and the reference quantity of exposure light (227, 228, 229), (b) a difference or a ratio between the current iris value and the target iris value (Fig. 38), and (c) the current iris value (427).
References Cited (Backward Citations)
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