Patent US3566140A successfully refreshed from Google Patents.
US3566140A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arrangement for measuring relative displacement utilizing relatively movable shutters which control the passage of modulated light
Assignee: Linde Sverige AB
•
Filing: 1969-03-26
•
Granted: 1971-02-23
•
Expires: 1989-03-26
Abstract
Abstract An apparatus for measuring the relative displacement of an object includes a stationary shutter and a movable shutter which control the light passing from a modulated light source to a light receiver. The movable shutter includes a plurality of secondary slots inclined relative to a primary slot in the stationary shutter so that light will pass through different portions of the primary slot depending on the position of the secondary slots relative thereto. The light receiver may comprise a plurality of photocells arranged relative to the primary slot such that the individual outputs thereof depend on the portion of the primary slot uncovered. The outputs of the photocells are each delayed by a different amount and are combined to produce a resultant signal whose phase is compared with the signal used to modulate the light source.
Inventors
- 👤 Carl-Erik Granqvist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:33
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/26; G01D5/32; G01D5/34; G01D5/36
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
176 words
An apparatus for measuring the relative displacement of an object in a predetermined direction comprising, a light source for transmitting light; signal generator means for modulating said light source with a primary signal; a light receiver for receiving the modulated light transmitted by said light source; first shutter means including a primary slot therein for controlling the light passing to said light receiver from said light source; second shutter means including a plurality of secondary slots therein for controlling the light passing through said primary slot to said light receiver, said secondary slots being inclined relative to said primary slot, and one to said shutter means being movable in said predetermined direction relative to the other of said shutter means; said light receiver comprising means responsive to light passing thereto as determined by the position of said secondary slots relative to said primary slot for producing an output signal related to the relative displacement of said second shutter means; and phase comparator means for measuring the phase difference between the output signal and said primary signal.
Claim 2
Independent Claim
176 words
An apparatus for measuring the relative displacement of an object in a predetermined direction comprising, a light source for transmitting light; signal generator means for modulating said light source with a primary signal; a light receiver for receiving the modulated light transmitted by said light source; first shutter means including a primary slot therein for controlling the light passing to said light receiver from said light source; second shutter means including a plurality of secondary slots therein for controlling the light passing through said primary slot to said light receiver, said secondary slots being inclined relative to said primary slot, and one to said shutter means being movable in said predetermined direction relative to the other of said shutter means; said light receiver comprising means responsive to light passing thereto as determined by the position of said secondary slots relative to said primary slot for producing an output signal related to the relative displacement of said second shutter means; and phase comparator means for measuring the phase difference between the output signal and said primary signal.
Claim 3
Dependent Claim
72 words
An apparatus as claimed in claim 1 wherein movement of said secondary slots relative to said primary slots permits passage of light through different portion of said primary slots and wherein said light receiver includes means for generating a plurality of secondary signals the individual phases of which correspond to different portions of set primary slot, said secondary apparatus further comprising means for combining said secondary signals to produce said output signal.
Claim 4
Dependent Claim
16 words
An apparatus as defined claimed in claim 2 wherein said primary signal comprises a sinusoidal signal.
Claim 5
Dependent Claim
38 words
An apparatus as claimed in claim 2 wherein said light receiver comprises a plurality of photocells and a plurality of delay lines individually connected to said photocells for providing different signal delays in said plurality of secondary signals.
Claim 6
Dependent Claim
40 words
An apparatus as claimed in claim 2 further comprising a heterodyning mixer including a first input connected to said signal geNerator means, a second input connected to a further signal generator means, and an output connected to said light source.
Claim 7
Dependent Claim
40 words
An apparatus as claimed in claim 5 further comprising a further heterodyning mixer including a first input connected to said additional generator means, a second input connected to said combining means and an output connected to said phase comparator means.
Claim 8
Dependent Claim
36 words
An apparatus as claimed in claim 1 wherein said light receiver comprises a plurality of light conductors of different lengths for conducting light to a common photocell, the output of said photocell comprising said output signal.
Claim 9
Dependent Claim
38 words
An apparatus as claimed in claim 7 further comprising signal generator means for modulating said light source with a primary signal and phase comparator means for measuring the phase difference between said output signal and said primary signal.
Claim 10
Dependent Claim
74 words
An apparatus as claimed in claim 8 further comprising a first heterodyning mixer including a first input connected to said generator means, a second input connected to a further generator means, and an output connected to said light source and a further heterodyning mixer including a first input connected to said further generator means, a second input connected to the output of said common photocell, and an output connected to said phase comparator means.
References Cited (Backward Citations)
US3167605A
Cited
US3446971A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-22 | 1974-08-24 | 1975-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-22 | 1978-08-24 | 1979-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-22 | 1982-08-24 | 1983-02-23 | $7700.00 | Window Closed / Lapsed |