US3785268A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Scanning type photographic film developing system and apparatus
Assignee: Individual
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Filing: 1973-01-19
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Granted: 1974-01-15
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Expires: 1993-01-19
Abstract
Abstract A system and apparatus is provided for developing photographic film such as X-ray film, for example, in a dental office, or in any other establishment. The system is capable of causing the film to be developed with any desired density, and within known limitations, regardless of whether the film has been over-exposed or under-exposed, and regardless of the temperature of the developing bath, and the age of the developing solution. The apparatus incorporates a control system which responds to the scanning of the exposed film in a developing solution by a radiant energy beam to which the particular film is relatively insensitive, and which causes the developing process to be terminated when a desired density is achieved. The system of the invention has a feature in that the very clear and very opaque areas, and other areas of no interest, are eliminated from the processing, and the desired density is established by processing the film between such minimums and maximums.
Inventors
- 👤 D Gregg
- 👤 C Pooley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:12
CPC Classifications
G; G03; G03D; G03D13/00; G03D13/007; G03D3/00; G03D3/08; G03D3/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
293 words
Photographic film developing apparatus and system including: a tank for a film developing solution; a source of radiant energy to which the film is relatively insensitive positioned to direct a beam of said energy through said solution in said tank; means for supporting a film to be developed in said tank in the path of said beam; scanning means coupled to said source for scanning said beam across said film; an energy detector positioned to receive the beam after it has passed through said flim for producing an electric signal representative of the intensity of said beam as received by said detector; and electrical circuit means coupled to said detector for developing an output indicative of when the density of the image developed on the film reaches a predetermined value, said circuitry including an input circuit coupled to said detector for developing a first signal which increases in amplitude as the brightness of the beam received by the detector increases from a reference level, and for developing a second signal which increases with amplitude as the brightness of the beam received by the detector decreaseS from a reference level, a first channel coupled to said input circuit for processing said first signal and including first peak detector means for producing a first output corresponding to the peak amplitude of the first signal, a second channel coupled to said input circuit for processing said second signal and including second peak detector means for producing a second output corresponding to the peak amplitude of the second signal; and an output circuit coupled to said first and second channels for developing the aforesaid output indicative of when the density of the image, or any portion of the image, developed on the film reaches a predetermined value.
Claim 2
Dependent Claim
293 words
Photographic film developing apparatus and system including: a tank for a film developing solution; a source of radiant energy to which the film is relatively insensitive positioned to direct a beam of said energy through said solution in said tank; means for supporting a film to be developed in said tank in the path of said beam; scanning means coupled to said source for scanning said beam across said film; an energy detector positioned to receive the beam after it has passed through said flim for producing an electric signal representative of the intensity of said beam as received by said detector; and electrical circuit means coupled to said detector for developing an output indicative of when the density of the image developed on the film reaches a predetermined value, said circuitry including an input circuit coupled to said detector for developing a first signal which increases in amplitude as the brightness of the beam received by the detector increases from a reference level, and for developing a second signal which increases with amplitude as the brightness of the beam received by the detector decreaseS from a reference level, a first channel coupled to said input circuit for processing said first signal and including first peak detector means for producing a first output corresponding to the peak amplitude of the first signal, a second channel coupled to said input circuit for processing said second signal and including second peak detector means for producing a second output corresponding to the peak amplitude of the second signal; and an output circuit coupled to said first and second channels for developing the aforesaid output indicative of when the density of the image, or any portion of the image, developed on the film reaches a predetermined value.
Claim 3
Dependent Claim
60 words
The apparatus and system defined in claim 1, and which includes first switching means included in said first channel for de-activating said first channel when the amplitude of said first signal exceeds a predetermined threshold, and second switching means included in said second channel for de-activating said second channel when the amplitude of said second signal exceeds a predetermined threshold.
Claim 4
Dependent Claim
46 words
The apparatus and system defined in claim 1, in which said output circuit includes differential comparator means connected to said first and second channels for causing said output circuit to develop its output when the differential between said first and second signals reaches a predetermined level.
Claim 5
Dependent Claim
39 words
The apparatus and system defined in claim 1, in which said output circuit includes differential comparator means connected to said second channel for causing said output circuit to develop said output when said second signal reaches a predetermined level.
Claim 6
Dependent Claim
38 words
The apparatus and system defined in claim 1, in which said output circuit includes differential comparator means connected to said first channel for causing said output circuit to develop said output when said first signal reaches zero amplitude.
Claim 7
Dependent Claim
52 words
The apparatus and system defined in claim 1, in which said output circuit includes differentiator means connected to one of said channels, and a gate circuit connected thereto, for preventing said output circuit from developing an output except during intervals when said first and second signals are decreasing in amplitude with time.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-14 | 1977-07-16 | 1978-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-14 | 1981-07-16 | 1982-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-14 | 1985-07-16 | 1986-01-15 | $7700.00 | Window Closed / Lapsed |