US3829222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device to introduce an optic measuring index at photoelectric detection of photographic plates
Assignee: Saab AB
•
Filing: 1973-03-26
•
Granted: 1974-08-13
•
Expires: 1993-03-26
Abstract
Abstract Density variation across a localized area of a photographic plate is detected by directing a beam through said area and thence onto a photoelectric detector through a narrow slot at the imaging plane. Relative motion is effected between the beam and the slot, hence detector output varies with density across the scanned zone. A fiducial mark carrier is in a separate beam (preferably emanating from the same source) which follows a path in bypass relation to the plate but which is combined with the image carrying beam at the slot. Light filters in the respective beams enable separate electronic processing of image beam signals and fiducial mark beam signals.
Inventors
- 👤 N Aslund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 00:25
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/28; G01J3/40; G01D; G01D5/00; G01D5/26; G01D5/32; G01D5/34; G01D5/341
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
409 words
Apparatus for producing electrical signals that correspond to variations in density detected during scanning of a small area of a photographic plate and by which the location on the plate of a particular part of such an area can be accurately ascertained, which apparatus comprises means for directing a first beam of light, of one spectral composition, along a defined path through a localized area of a photographic plate and through lens means for bringing the beam to a focus at an imaging plane, means at the imaging plane defining a scanning slot in said defined path, a photoelectric detector in said path upon which falls that portion of the beam that passes through the scanning slot and which is responsive substantially only to light of said one spectral composition and produces an electrical output that corresponds to the intensity of such light falling upon it, means for directing a second beam of light, of a substantially different spectral composition, along a second defined path having one part which is in bypassing relation to the photographic plate and which traverses means for producing an image of a fiducial mark and having another part which coincides with a part of the path of the first beam and extends through the scanning slot, another photoelectric detector, responsive substantially only to light of said different spectral composition and arranged to receive light of said second beam that has passed through said scanning slot, and means for effecting periodic relative motion between said beams and the scanning slot means in directions transverse to the length of the scanning slot, said apparatus being characterized by: A. said means for producing an image of a fiducial mark comprising an element that has at least one opaque area and at least one transparent area, said areas being contiguous to one another along a line parallel to the scanning slot; B. means for effecting relative adjustment between the scanning slot and said lens means so that an image on any area of a photographic plate through which said first mentioned beam passes can be brought to focus at the plane of the scanning slot notwithstanding lack of flatness in the photographic plate; and C. other lens means in said one part of the second defined path for bringing the image of the fiducial mark to a focus at the plane of the scanning slot independently of the focus of the image carried by the first mentioned beam.
Claim 2
Dependent Claim
409 words
Apparatus for producing electrical signals that correspond to variations in density detected during scanning of a small area of a photographic plate and by which the location on the plate of a particular part of such an area can be accurately ascertained, which apparatus comprises means for directing a first beam of light, of one spectral composition, along a defined path through a localized area of a photographic plate and through lens means for bringing the beam to a focus at an imaging plane, means at the imaging plane defining a scanning slot in said defined path, a photoelectric detector in said path upon which falls that portion of the beam that passes through the scanning slot and which is responsive substantially only to light of said one spectral composition and produces an electrical output that corresponds to the intensity of such light falling upon it, means for directing a second beam of light, of a substantially different spectral composition, along a second defined path having one part which is in bypassing relation to the photographic plate and which traverses means for producing an image of a fiducial mark and having another part which coincides with a part of the path of the first beam and extends through the scanning slot, another photoelectric detector, responsive substantially only to light of said different spectral composition and arranged to receive light of said second beam that has passed through said scanning slot, and means for effecting periodic relative motion between said beams and the scanning slot means in directions transverse to the length of the scanning slot, said apparatus being characterized by: A. said means for producing an image of a fiducial mark comprising an element that has at least one opaque area and at least one transparent area, said areas being contiguous to one another along a line parallel to the scanning slot; B. means for effecting relative adjustment between the scanning slot and said lens means so that an image on any area of a photographic plate through which said first mentioned beam passes can be brought to focus at the plane of the scanning slot notwithstanding lack of flatness in the photographic plate; and C. other lens means in said one part of the second defined path for bringing the image of the fiducial mark to a focus at the plane of the scanning slot independently of the focus of the image carried by the first mentioned beam.
Claim 3
Dependent Claim
47 words
said other lens means having a substantially large depth of focal field, such that the image of the fiducial mark is in focus at the scanning slot in all positions of adjustment of the scanning slot means along said part of the path of the first beam.
Claim 4
Dependent Claim
47 words
said other lens means having a substantially large depth of focal field, such that the image of the fiducial mark is in focus at the scanning slot in all positions of adjustment of the scanning slot means along said part of the path of the first beam.
Claim 5
Dependent Claim
8 words
The apparatus of claim 1, further characterized by:
Claim 6
Dependent Claim
51 words
a plurality of uniform substantially smaller squares, each having its edges parallel to said edges of the fiducial mark defining zone, said squares being spaced from one another at uniform intervals and being arranged in uniform rows that extend parallel to both of said edges of the fiducial mark defining zone.
Claim 7
Dependent Claim
51 words
a plurality of uniform substantially smaller squares, each having its edges parallel to said edges of the fiducial mark defining zone, said squares being spaced from one another at uniform intervals and being arranged in uniform rows that extend parallel to both of said edges of the fiducial mark defining zone.
Claim 8
Dependent Claim
168 words
The apparatus of claim 1, further characterized by: D. means comprising beam dividing means defining a branch path portion for each of said two beams and in at least a part of which the two beams coincide; E. means defining a second scanning slot in said part of said branch path portion and at a second imaging plane, said second scanning slot being oriented transversely to the first mentioned scanning slot relative to the images carried by the beams; F. means for bringing to a focus at said second imaging plane the images carried by both of said two beams; G. means for effecting periodic relative motion between said second scanning slot means and said beams in said part of said branch path portion, in directions transverse to the length of said second scanning slot; and H. said opaque and transparent areas of said element being also contiguous to one another along a line perpEndicular to the first mentioned line so that one of said areas is quadrant-like.
Claim 9
Dependent Claim
40 words
The apparatus of claim 1, further characterized by: E. semi-reflector means between the scanning slot and the detectors for forming a pair of counterparts of the coinciding beams and directing each of said counterparts to one of the photoelectric detectors.
Claim 10
Dependent Claim
57 words
The apparatus of claim 2, further characterized by: said fiducial mark image producing means comprising an element that has areas of a kind to block light, the remaining areas of said element being of a kind to pass light, the areas of said element that are of one of said kinds being arranged in the form of
Claim 11
Dependent Claim
54 words
The apparatus of claim 5, further characterized by: said squares being so arranged as to also be in rows which extend perpendicularly to the bisector of the right angle defined by said edges of the fiducial mark defining zone, and certain of said squares being opposite at least one of the last mentioned edges.
Claim 12
Dependent Claim
36 words
The apparatus of claim 6, wherein each of the last mentioned rows of squares extends substantially equal distances to opposite sides of said bisector so that there are squares opposite both of said last mentioned edges.
Claim 13
Dependent Claim
230 words
Apparatus wherein light from a light source is directed in a beam through a small area of a photographic plate and thence onto photo-responsive detector means for producing signals corresponding to variations in density across said area of the photographic plate, said apparatus being characterized by: A. means for bifurcating said beam into a pair of beam components and directing each beam component along one of a pair of path portions in each of which there is an imaging plane at which the beam component is in focus; B. means at each imaging plane defining a scanning slot in said defined path through which the beam component passes to detector means, one of said scanning slots being transverse to the other relative to the image carried by the beam components; C. means for directing a second beam of light through means for producing an image of a fiducial mark; D. means for bifurcating said second beam and for directing its bifurcated components along path portions that coincide in substantial part with said path portions of the first mentioned beam, through the respective scanning slots and with the bifurcated components of the second beam in focus at said imaging planes; and E. means for effecting periodic relative motion between each of the scanning slot means and the beam components passing therethrough, in directions transverse to the length of the scanning slot.
Claim 14
Dependent Claim
230 words
Apparatus wherein light from a light source is directed in a beam through a small area of a photographic plate and thence onto photo-responsive detector means for producing signals corresponding to variations in density across said area of the photographic plate, said apparatus being characterized by: A. means for bifurcating said beam into a pair of beam components and directing each beam component along one of a pair of path portions in each of which there is an imaging plane at which the beam component is in focus; B. means at each imaging plane defining a scanning slot in said defined path through which the beam component passes to detector means, one of said scanning slots being transverse to the other relative to the image carried by the beam components; C. means for directing a second beam of light through means for producing an image of a fiducial mark; D. means for bifurcating said second beam and for directing its bifurcated components along path portions that coincide in substantial part with said path portions of the first mentioned beam, through the respective scanning slots and with the bifurcated components of the second beam in focus at said imaging planes; and E. means for effecting periodic relative motion between each of the scanning slot means and the beam components passing therethrough, in directions transverse to the length of the scanning slot.
Claim 15
Dependent Claim
75 words
The apparatus of claim 8, further characterized by: F. said fiducial mark image producing means comprising an element having an opaque area with a pair of sharply defined straight edges that are at right angles to one another so that a scan transverse to each such edge causes a sharply defined change in output level as the scan crosses the edge, to define a fiducial mark, and such changes occur in both directions of scanning.
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) | 1977-08-12 | 1978-02-11 | 1978-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-12 | 1982-02-11 | 1982-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-12 | 1986-02-11 | 1986-08-13 | $7700.00 | Window Closed / Lapsed |