Patent US4032933A successfully refreshed from Google Patents.
US4032933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Indication system of a camera
Assignee: Canon Inc
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Filing: 1975-03-03
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Granted: 1977-06-28
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Expires: 1995-03-03
Abstract
Abstract A camera having an indication system to determine suitable diaphragm aperture value by measuring the light penetrating through a photographing lens and to indicate the same digitally, wherein when said diaphragm aperture value exceeds the limit value of exposure control of a camera, a warning indication is given by the indication means to indicate the fact that the diaphragm aperture value is outside of control limit, and the number of input/output lead wires to the indication means is reduced. Thus simplifying the set-up.
Inventors
- 👤 Tadashi Ito
- 👤 Masanori Uchidoi
- 👤 Tetsuya Taguchi
- 👤 Tokuichi Tunekawa
- 👤 Hiroshi Aizawa
- 👤 Yoshiyuki Takishima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:59
CPC Classifications
G; G03; G03B; G03B17/00; G03B17/18; G03B17/20
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
189 words
An indication system of a camera comprising: means to measure the brightness of an object; means to set photographing information; operating means coupled to said light measuring means and said photographing information setting means for obtaining an exposure value which corresponds to the output of both said means; analog-digital conversion means coupled to said operating means to generate a digital signal which corresponds to the exposure value, wherein said conversion means has a plurality of detection means for a plural number of steps, one of which is placed in an activated state depending on said exposure value; a plurality of diode arrays, each one of which is connected respectively to a corresponding one of said detection means; an indication means connected to said diode arrays to digitally indicate said exposure value; a pulse generation means; and an exposure limit signal generation means responsive to said pulse generation means and to the last step of said detection means, wherein said signal generation means generates a signal to control the lighting state of said indication means when the output signals of both said means are supplied to said signal generation means.
Claim 2
Dependent Claim
189 words
An indication system of a camera comprising: means to measure the brightness of an object; means to set photographing information; operating means coupled to said light measuring means and said photographing information setting means for obtaining an exposure value which corresponds to the output of both said means; analog-digital conversion means coupled to said operating means to generate a digital signal which corresponds to the exposure value, wherein said conversion means has a plurality of detection means for a plural number of steps, one of which is placed in an activated state depending on said exposure value; a plurality of diode arrays, each one of which is connected respectively to a corresponding one of said detection means; an indication means connected to said diode arrays to digitally indicate said exposure value; a pulse generation means; and an exposure limit signal generation means responsive to said pulse generation means and to the last step of said detection means, wherein said signal generation means generates a signal to control the lighting state of said indication means when the output signals of both said means are supplied to said signal generation means.
Claim 3
Dependent Claim
38 words
An indication system according to claim 1, in which said diode arrays comprise a plural number of diodes being connected in parallel, wherein said plural number of diodes and said detection means are connected by one lead wire.
Claim 4
Dependent Claim
27 words
An indication system according to claim 2, in which said indication means has a plural number of 7-segment indication elements, which are connected to the said diodes.
Claim 5
Dependent Claim
51 words
An indication system according to claim 1, which further comprises another exposure limit signal generation means coupled to the first step of the detection means, wherein said generation means generates a signal to control the lighting state of said indication means when the output signals of both said means are supplied.
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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) | 1980-06-27 | 1980-12-27 | 1981-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-27 | 1984-12-27 | 1985-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-27 | 1988-12-27 | 1989-06-28 | $7700.00 | Window Closed / Lapsed |