US3860328A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Measuring attenuator for an optical null spectrophotometer
Assignee: Pye Electronic Products Ltd
•
Filing: 1973-07-06
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Granted: 1975-01-14
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Expires: 1993-07-06
Abstract
Abstract An adjustable geometry measuring attenuator for an optical null spectrophotometer. The attenuator has two opaque plates mounted to provide a wedge shaped aperture which is movable across the reference radiation beam. At each end of the wedge the plates are mounted by rollers on a pair of parallel tracks whose spacing and hence the relative positions of the two plates can be adjusted by rotation of links connecting the tracks of each pair. This rotation is achieved by means of a string which is fixed relative to the pair of tracks at the narrow end of the wedge and passes over a pulley on the pair of tracks at the wide end of the wedge. A control knob on the instrument calibrated in terms of percentage ''''back-off'''' or the lower transmittance limit attached to the end of the string leading from the narrow end of the wedge and when this end of the string is moved the spacing of the plates is altered whilst keeping the wedge angle the same. Another control knob on the instrument calibrated in terms of scale expansion is attached to the end of the string leading from the wide end of the wedge and when this end of the string is moved the angle of the wedge is altered.
Inventors
- 👤 John Richard Firth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:44
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/02; G01J3/04; G01J1/00; G01J1/10; G01J1/20; G01J1/22; G01J1/24; G01J3/28; G01J2003/2866
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
95 words
A measuring attenuator for an optical null spectrophotometer, in which two opaque plates are mounted so as to provide a wedge shaped space therebetween, in which the two plates are movable together substantially along the axis of symmetry of the wedge to perform the measuring operation between lower and upper transmittance limits, and in which means are provideD which enable the relative positions of the plates to be adjusted from a point remote from the attenuator so as to change both the lower and upper transmittance limits whilst keeping the same range between said limits.
Claim 2
Dependent Claim
95 words
A measuring attenuator for an optical null spectrophotometer, in which two opaque plates are mounted so as to provide a wedge shaped space therebetween, in which the two plates are movable together substantially along the axis of symmetry of the wedge to perform the measuring operation between lower and upper transmittance limits, and in which means are provideD which enable the relative positions of the plates to be adjusted from a point remote from the attenuator so as to change both the lower and upper transmittance limits whilst keeping the same range between said limits.
Claim 3
Dependent Claim
56 words
A measuring attenuator as claimed in claim 1, in which the wedge shaped space is substantially straight edged, and in which means are also provided which enable the relative positions of the plates to be adjusted from another point remote from the attenuator so as to change the range between the lower and upper transmittance limits.
Claim 4
Dependent Claim
218 words
A radiation beam intensity measuring attenuator for an optical null spectrophotometer, in which two opaque plates each having a substantially straight edge are located so as to provide a wedge shaped space between said edges, in which the two plates are movable together between first and second limit positions substantially along the axis of symmetry of the wedge to perform the measuring operation, in which both plates are mounted on first adjustable mounting means which determine the separation of the plates at the position of the radiation beam when the plates are at said first limit position and hence the lower transmittance limit of the attenuator, in which both plates are also mounted on second adjustable mounting means which determine the separation of the plates at the position of the radiation beam when the plates are at said second limit position and hence the upper transmittance limit of the attenuator, and in which the first and second adjustable mounting means are interconnected so that they can be adjusted together from a point remote from the attenuator to change both the lower and upper transmittance limits whilst keeping the same range between said limits and so that the second mounting means can also be adjusted from another point remote from the attenuator to change the upper transmittance limit alone.
Claim 5
Dependent Claim
218 words
A radiation beam intensity measuring attenuator for an optical null spectrophotometer, in which two opaque plates each having a substantially straight edge are located so as to provide a wedge shaped space between said edges, in which the two plates are movable together between first and second limit positions substantially along the axis of symmetry of the wedge to perform the measuring operation, in which both plates are mounted on first adjustable mounting means which determine the separation of the plates at the position of the radiation beam when the plates are at said first limit position and hence the lower transmittance limit of the attenuator, in which both plates are also mounted on second adjustable mounting means which determine the separation of the plates at the position of the radiation beam when the plates are at said second limit position and hence the upper transmittance limit of the attenuator, and in which the first and second adjustable mounting means are interconnected so that they can be adjusted together from a point remote from the attenuator to change both the lower and upper transmittance limits whilst keeping the same range between said limits and so that the second mounting means can also be adjusted from another point remote from the attenuator to change the upper transmittance limit alone.
Claim 6
Dependent Claim
175 words
A measuring attenuator as claimed in claim 3, in which the first and second mounting means each include a pair of parallel tracks, the two pairs of tracks being parallel and the two plates being movable together on the tracks between said first and second limit positions, in which the tracks of each pair are linked by means which are rotatable for changing the spacing between the tracks of that pair, and in which a string interconnects the first and second mounting means and extends at each end to a point remote from the attenuator, the interconnection being such that if one end of the string extending from the first mounting means is moved while the other end is anchored then the spacing between the tracks of both the first and second mounting means will be changed whereas if the said other end of the string extending from the second mounting means is moved while said one end is anchored then the spacing between the tracks of the second mounting means alone will be changed.
Claim 7
Dependent Claim
32 words
A measuring attenuator as claimed in claim 4, and in which the interconnecting string is fixed relative to the first mounting means and passes over a pulley on the second mounting means.
Claim 8
Dependent Claim
39 words
A measuring attenuator as claimed in claim 4, and in which spring means are fixed to the second mounting means which tend to close both pairs of tracks and hence stabilises them at any position set by said string.
Claim 9
Dependent Claim
50 words
A measuring attenuator as claimed in claim 4, in which said one end of the string is linked to a control calibrated in terms of the lower transmittance limit, and in which said other end of the string is linked to a control calibrated in terms of scale expansion factor.
Claim 10
Dependent Claim
54 words
A measuring attenuator as claimed in claim 4, in which at each end of the pair of plates both plates are attached by pivotally mounted coupling pieces to a driving string, and in which the two driving strings are included in a continuous loop of a servo system adapted to operate the measuring attenuator.
References Cited (Backward Citations)
US3529898A
Cited
US3685885A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-13 | 1978-07-15 | 1979-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-13 | 1982-07-15 | 1983-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-13 | 1986-07-15 | 1987-01-14 | $7700.00 | Window Closed / Lapsed |