Patent US3596253A successfully refreshed from Google Patents.
US3596253A
Expired / Lapsed
US
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Two-stage retrieval microfilm reader
Assignee: DSI SYSTEMS Inc
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Filing: 1969-04-08
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Granted: 1971-07-27
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Expires: 1989-04-08
Abstract
Abstract A microfilm reader of the cartridge type utilizing spots on the film frames of the cartridge in cooperation with photosensitive detectors to mintor the movement of the frames. The photosensitive detectors control the drive mechanism of the cartridge in a manner such that the mechanism may be operated in accordance with a coded input signal corresponding to a particular film frame desired to be viewed. The input signal may be applied either locally from a keyboard, or from a remote source. The signal is coded to correspond to the desired film frame number. The microfilm reader is provided with circuits to compare the input signal data with data derived from the previous movement of the film frames and to then drive the film to the frame corresponding to the input signal data. The microfilm reader may be set to operate either in the above mode, or in an incremental mode wherein the film is moved in either a forward direction or a reverse direction in increments of a selected definite number of film frames.
Inventors
- 👤 Robert W Ruth
- 👤 Bennett S Le Bow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:27
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/10; G03B21/11; G03B21/111; G03B21/113; G06; G06K; G06K17/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
296 words
A microfilm viewer for automatically indexing a strip of microfilm to a desired viewing position wherein said microfilm strip includes a plurality of longitudinally spaced index markers at regular intervals to signify the location of successive film frames disposed thereon, said viewer comprising: optical means for projecting a display of at least one of said film frames when disposed at a predetermined position, forward motion means for moving said microfilm strip in a first forward direction relative to said predetermined position, reverse motion means for moving said microfilm strip in a second reverse direction relative to said predetermined position, detecting means for detecting said index markers and for producing a page signal each time one of said markers passes said detecting means, up-down counter means for adding or subtracting said page signals depending upon whether said forward motion means or said reverse motion means is activated respectively to thereby maintain a contents indicative of the present position of said successive film frames with respect to said predetermined position, an input means for accepting digital input signals representing a particular position of said filmstrip for which a display is desired, a first input counter operatively connected to said input means for counting from an initial contents corresponding to said input signals, a second present position counter operatively connected to said up-down counter for counting from an initial contents corresponding to the present position of said filmstrip, oscillator means operatively connected to said first and second counters for simultaneously incrementing the conTents thereof, and logic means connected to said first and second counters for sensing which counter first attains a predetermined contents to thereby determine whether said forward motion means or said reverse motion means should be activated to most expeditiously reach the desired position of said filmstrip.
Claim 2
Dependent Claim
296 words
A microfilm viewer for automatically indexing a strip of microfilm to a desired viewing position wherein said microfilm strip includes a plurality of longitudinally spaced index markers at regular intervals to signify the location of successive film frames disposed thereon, said viewer comprising: optical means for projecting a display of at least one of said film frames when disposed at a predetermined position, forward motion means for moving said microfilm strip in a first forward direction relative to said predetermined position, reverse motion means for moving said microfilm strip in a second reverse direction relative to said predetermined position, detecting means for detecting said index markers and for producing a page signal each time one of said markers passes said detecting means, up-down counter means for adding or subtracting said page signals depending upon whether said forward motion means or said reverse motion means is activated respectively to thereby maintain a contents indicative of the present position of said successive film frames with respect to said predetermined position, an input means for accepting digital input signals representing a particular position of said filmstrip for which a display is desired, a first input counter operatively connected to said input means for counting from an initial contents corresponding to said input signals, a second present position counter operatively connected to said up-down counter for counting from an initial contents corresponding to the present position of said filmstrip, oscillator means operatively connected to said first and second counters for simultaneously incrementing the conTents thereof, and logic means connected to said first and second counters for sensing which counter first attains a predetermined contents to thereby determine whether said forward motion means or said reverse motion means should be activated to most expeditiously reach the desired position of said filmstrip.
Claim 3
Dependent Claim
102 words
A microfilm viewer as in claim 1 including: means for selectively activating said forward motion means or said reverse motion means in response to the output of said logic means, and means for causing said page signals to further increment the one of said first or second counters that did not first reach said predetermined contents, and brake means for stopping the one of said motion means that has been activated when the other one of said first or second counters reaches said predetermined contents thereby insuring that said desired portion of said filmstrip is positioned at said predetermined position for display.
Claim 4
Dependent Claim
40 words
A microfilm viewer as in claim 2 further including: slowing means for sensing when said other one of said first or second counters is approaching said predetermined contents and for slowing said motion means in response thereto to prevent overshoot.
Claim 5
Dependent Claim
99 words
A microfilm viewer as in claim 1 for use with microfilm strips having at least first and second index markers at predetermined relative dispositions for each of said regular intervals on the strip of film and wherein said detecting means includes: first means positioned for responding to said first index marker, second means positioned for responding to said second index marker, and common detector means operatively connected to said first and second means for producing said page signal only if outputs from said first and second means correspond to said predetermined relative dispositions to thereby prevent spurious page signals.
Claim 6
Dependent Claim
23 words
A microfilm viewer as in claim 1 wherein said input means includes external automatic digital computing means for generating said digital input signals.
Claim 7
Dependent Claim
56 words
A microfilm viewer as in claim 1 wherein said input means comprises: a manually operable keyboard for keying in information representing a desired microfilm frame and for producing said digital input signals in response thereto, and a register means for temporarily storing and ordering said digital input signals for subsequent transfer to said first input counter.
Claim 8
Dependent Claim
165 words
An improvement for an automatically indexable viewer which permits automatic indexing with use of only simple elementary index spots on a strip of microfilm, said improvement comprising: means for detecting said index spots as the film is advanced in either a forward or reverse direction and for producing page pulses in response thereto, up-down counter means for adding or subtracting said page pulses depending upon whether said film is advancing in either said forward or said reverse direction respectively to thereby maintain an instantaneous contents representing the present position of said strip of microfilm, input means for accepting a particular desired position of the strip of microfilm for which a display is desired, and means operatively connected to said up-down counter means and to said input means for comparing said present position to said desired position and for producing an output indicating whether said strip of microfilm should be advanced in said forward or reverse direction to most expeditiously reach and display said desired position.
Claim 9
Dependent Claim
165 words
An improvement for an automatically indexable viewer which permits automatic indexing with use of only simple elementary index spots on a strip of microfilm, said improvement comprising: means for detecting said index spots as the film is advanced in either a forward or reverse direction and for producing page pulses in response thereto, up-down counter means for adding or subtracting said page pulses depending upon whether said film is advancing in either said forward or said reverse direction respectively to thereby maintain an instantaneous contents representing the present position of said strip of microfilm, input means for accepting a particular desired position of the strip of microfilm for which a display is desired, and means operatively connected to said up-down counter means and to said input means for comparing said present position to said desired position and for producing an output indicating whether said strip of microfilm should be advanced in said forward or reverse direction to most expeditiously reach and display said desired position.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |