US4386851A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Instrument for measuring or marking out distances from a line or a plane
Assignee: Individual
•
Filing: 1980-09-03
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Granted: 1983-06-07
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Expires: 2000-09-03
Abstract
Abstract Instrument for measuring the distances of points from a plane or a straight line defined by means of the instrument. The instrument may also be used in marking output points from a plane or a straight line. The instrument functions by forming at least two mirror images of a measuring object in such a manner that these images are differently oriented when viewed. This is accomplished in the simplest embodiment of the instrument by a prism whose front face is semi-reflecting whereas the other faces are perpendicular to each other and totally reflecting. If the measuring object is not on the defined plane or line this will show up as a displacement of the differently oriented mirror images in relation to each other. The substantial novelty of the instrument is that all the images the relative displacement of which are employed for the read-out are mirror images of the measuring object and are formed without the need for focussing optical components such as lenses and concave mirrors.
Inventors
- 👤 Stig K. Eidorff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:19
CPC Classifications
G; G01; G01C; G01C15/00; G01C5/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
132 words
Instrument for measuring or marking out the distance of a point from a basic plane or line comprising: a definition sub-unit including at least two and at the most three mutually perpendicular planar reflecting mirror surfaces enclosing between them an angle bisectrix defining said basic plane or line, and a planar semitransparent mirror surface facing said reflecting mirror surfaces and intersecting said bisectrix, an object sub-unit including a visual object adapted to be held in a predetermined relation to said point, a viewing sub-unit arranged to observe through the intermediary of said definition sub-unit a pair of oppositely oriented mirror images of said visual object and to register their relative position as a measure of said distance, and said object sub-unit being optically arranged between the definition sub-unit and the viewing sub-unit.
Claim 2
Dependent Claim
132 words
Instrument for measuring or marking out the distance of a point from a basic plane or line comprising: a definition sub-unit including at least two and at the most three mutually perpendicular planar reflecting mirror surfaces enclosing between them an angle bisectrix defining said basic plane or line, and a planar semitransparent mirror surface facing said reflecting mirror surfaces and intersecting said bisectrix, an object sub-unit including a visual object adapted to be held in a predetermined relation to said point, a viewing sub-unit arranged to observe through the intermediary of said definition sub-unit a pair of oppositely oriented mirror images of said visual object and to register their relative position as a measure of said distance, and said object sub-unit being optically arranged between the definition sub-unit and the viewing sub-unit.
Claim 3
Dependent Claim
22 words
Instrument as claimed in claim 1, wherein said semitransparent mirror surface of said definition sub-unit intersects and is perpendicular to said bisectrix.
Claim 4
Dependent Claim
24 words
Instrument as claimed in claim 1, wherein said semitransparent mirror of said definition sub-unit intersects and forms an angle of 45° with said bisectrix.
Claim 5
Dependent Claim
56 words
Instrument as claimed in claim 3, wherein said bisectrix of said definition sub-unit is perpendicular to said basic plane or line, and wherein the mirror images of said visual object are viewed via at least one reflecting surface in said definition under deflecting the line of sight of said viewing sub-unit through an angle of 90°.
Claim 6
Dependent Claim
125 words
Instrument as claimed in claim 1, wherein said semitransparent mirror surface of said definition sub-unit includes an obtuse angle with said bisectrix, and further comprising a second pair of reflecting mirror surfaces being provided one on either side of said bisectrix including equal angles with the plane of said semitransparent mirror surface, a third reflecting mirror surface being provided parallel to said bisectrix and facing said second pair of reflecting surfaces so as to reflect light rays received from one of the second pair of reflecting surfaces onto the other, an assembly comprising said mutually perpendicular reflecting surfaces, said second pair of reflecting surfaces, and said semitransparent mirror surface being pivotal as a whole about an axis perpendicular to and intersecting said third mirror surface.
Claim 7
Dependent Claim
59 words
Instrument as claimed in claim 1, wherein at least a portion of an optical axis of said viewing sub-unit is parallel to said basic plane or line, an optical axis of said object sub-unit being perpendicular to said basic plane or line, and a semitransparent mirror being provided at the intersection of said axes bisecting the angle between them.
Claim 8
Dependent Claim
27 words
Instrument as claimed in claim 1, wherein said object sub-unit and said viewing sub-unit are united into an assembly, whereas said definition sub-unit is a separate unit.
Claim 9
Dependent Claim
72 words
Instrument as claimed in claim 1, further comprising filters having different transmittance inserted in the light paths from said object sub-unit via said definition sub-unit to said viewing sub-unit, said filters being provided in sections of the light paths specific for each orientation of said mirror images so that differently oriented images are composed of light having different frequency bands, said viewing sub-unit comprising two receptors sensitive to a respective frequency band.
Claim 10
Dependent Claim
70 words
Instrument as claimed in claim 1, further comprising filters having different reflectance inserted in the light paths from said object sub-unit via said definition sub-unit to said viewing sub-unit, said filters being provided in sections of the light paths specific for each orientation of said mirror images, so that differently oriented images are composed of light having different polarization, said viewing sub-unit comprising two receptors sensitive to a respective polarization.
Claim 11
Dependent Claim
83 words
Instrument as claimed in claim 1, further comprising periodically operated shutters having the same periodicity but different phases inserted in the light paths from said object sub-unit via said definition sub-unit to said viewing sub-unit, said shutters being provided in sections of the light paths specific for each orientation of said mirror images, so that differently oriented images are composed of light pulses being displaced in time from each other, said viewing sub-unit comprising two sensors registering the phase difference between said pulses.
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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) | 1986-06-06 | 1986-12-06 | 1987-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-06-06 | 1990-12-06 | 1991-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-06-06 | 1994-12-06 | 1995-06-07 | $7700.00 | Window Closed / Lapsed |