US6320615B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light level detecting and indicating method for image photographing and recording
Assignee: Samsung Electronics Co Ltd
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Filing: 1996-11-21
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Granted: 2001-11-20
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Expires: 2016-11-21
Abstract
Abstract A light level detecting method uses an automatic gain control of an electrically transformed image signal, thereby obviating the need for a separate light sensor. Instead, the method makes use of the image signal in the recording process. The light detecting and indicating method includes the steps of: (a) setting up a reference value corresponding to an amount of light which requires an automatic gain control; (b) measuring the amount of light of an optical input signal; (c) calculating a comparative value corresponding to the amount of light, where the comparative value controls the performance of the automatic gain control; (d) comparing the reference value with the comparative value; and (e) determining that the amount of light is insufficient when the result of the comparing step falls within a predetermined gain control range.
Inventors
- 👤 Ji-ho Kim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:28
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/70; H04N23/75; H04N23/76
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
139 words
A light detecting method employed in an image photographing and recording device, said light detecting method comprising: (a) setting a reference value and a corresponding gain control range as a function of an input optical signal, said reference value corresponding to the highest level of light which requires an automatic gain control; (b) measuring a level of light of the input optical signal; (c) calculating a comparative value corresponding to the measured level of light, wherein said comparative value controls the performance of said automatic gain control; (d) comparing said reference value with said comparative value; and (e) determining that an amount of light is insufficient when the result of said comparing step falls within said gain control range, and (f) indicating whether or not the amount of light is sufficient according to the result of said step (e).
Claim 2
Dependent Claim
139 words
A light detecting method employed in an image photographing and recording device, said light detecting method comprising: (a) setting a reference value and a corresponding gain control range as a function of an input optical signal, said reference value corresponding to the highest level of light which requires an automatic gain control; (b) measuring a level of light of the input optical signal; (c) calculating a comparative value corresponding to the measured level of light, wherein said comparative value controls the performance of said automatic gain control; (d) comparing said reference value with said comparative value; and (e) determining that an amount of light is insufficient when the result of said comparing step falls within said gain control range, and (f) indicating whether or not the amount of light is sufficient according to the result of said step (e).
Claim 3
Dependent Claim
34 words
A light detecting method as claimed in claim 1 , wherein in step (e) it is determined that said amount of light is insufficient when said comparative value is smaller than said reference value.
Claim 4
Dependent Claim
32 words
A light detecting method as claimed in claim 1 , wherein said amount of light is measured by determining a mean value of a specific sampling block of said input optical signal.
Claim 5
Dependent Claim
81 words
A light detecting method as claimed in claim 1 , wherein in step (e) said gain control range is subdivided into a first range and a second range, and wherein when the result of said comparing step falls within said first range it is concluded that insufficient light is available for taking a picture without performing gain control, and when the result of said comparing step falls within said second range it is concluded that the available light renders photography impossible.
Claim 6
Dependent Claim
50 words
A light detecting method as claimed in claim 4 , further comprising a step (f) for indicating that insufficient light is available for taking a picture without AGC by turning on a luminous element, and for indicating that the available light renders photography impossible by making said luminous element flicker.
Claim 7
Dependent Claim
116 words
A microprocessor for photographic image recorders, said microprocessor preprogrammed to perform the steps comprising: (a) setting a reference value and a corresponding gain control range as a function of an input optical signal, said reference value corresponding to the highest level of light which requires an automatic gain control; (b) measuring a level of light of the input optical signal; (c) calculating a comparative value corresponding to the measured level of light, wherein said comparative value controls the performance of said automatic gain control; (d) comparing said reference value with said comparative value; an (e) determining that an amount of light is insufficient when the result of said comparing step falls within said gain control range.
Claim 8
Dependent Claim
116 words
A microprocessor for photographic image recorders, said microprocessor preprogrammed to perform the steps comprising: (a) setting a reference value and a corresponding gain control range as a function of an input optical signal, said reference value corresponding to the highest level of light which requires an automatic gain control; (b) measuring a level of light of the input optical signal; (c) calculating a comparative value corresponding to the measured level of light, wherein said comparative value controls the performance of said automatic gain control; (d) comparing said reference value with said comparative value; an (e) determining that an amount of light is insufficient when the result of said comparing step falls within said gain control range.
Claim 9
Dependent Claim
28 words
The microprocessor of claim 6 , wherein said amount of light is measured by determining a mean value of a specific sampling block of said input optical signal.
Claim 10
Dependent Claim
32 words
The microprocessor of claim 6 , wherein said microprocessor further performs a step (f) for indicating whether or not the amount of light is sufficient according to a result of step (e).
Claim 11
Dependent Claim
77 words
The microprocessor of claim 6 , wherein in step (e) said gain control range is subdivided into a first range and a second range, and wherein when the result of said comparing step falls within said first range it is concluded that insufficient light is available for photography without performing gain control, and when the result of said comparing step falls within said second range it is concluded that the level of available light renders photographing impossible.
Claim 12
Dependent Claim
50 words
The microprocessor of claim 9 , wherein said microprocessor further performs a step (f) for indicating that insufficient light is available for photography without AGC by turning on a luminous element, and for indicating that the available light level is too low for photography by making said luminous element flicker.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-11-19 | 2005-05-21 | 2005-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-11-19 | 2009-05-21 | 2009-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-11-19 | 2013-05-21 | 2013-11-20 | $7700.00 | Window Closed / Lapsed |