US3728025A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical distance measuring equipment
Assignee: Cubic Corp
•
Filing: 1971-03-08
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Granted: 1973-04-17
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Expires: 1991-03-08
Abstract
Abstract Distance measuring equipment that utilizes a light beam that is intensity modulated by a carrier frequency which is frequency modulated by subcarrier frequencies to provide accurate fine, medium, and coarse distance measurements by detecting the phase shift of these carrier and subcarrier frequencies as a function of distance, and which system includes a cross coupling light transmission means for removing internal delay phase shift error, and that employs a light attenuating device to equalize the intensity of the cross coupling illumination with the return illumination received, and that employs a light transmitter having a substantially planar light source.
Inventors
- 👤 T Madigan
- 👤 R Stone
- 👤 D Dunn
- 👤 W Holzer
- 👤 R Sweet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:20
CPC Classifications
G; G01; G01S; G01S17/00; G01S17/02; G01S17/06; G01S17/08; G01S17/32; G01S7/00; G01S7/48; G01S7/497
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
163 words
In an optical distance measuring device, a light source, transmitter means for sending a continuous light beam from said source toward a light reflecting object whose distance is to be measured, first means for generating a carrier frequency, second means for frequency modulating said carrier frequency by a sub-carrier frequency, means for simultaneously modulating the intensity of said continuous light beam by said carrier frequency and said subcarrier frequency, receiver means for receiving and detecting the intensity of said light beam from said reflecting object and providing data output signals, means for cross coupling said carrier frequency and sub-carrier frequency from said first and second means to said receiver means, means for determining the relative phase shifts of said carrier frequency and said sub-carrier frequency reflected in the changes in intensity of the outgoing and incoming continuous light beam, and means for combining the determined phase shift of said carrier frequency and the phase shift of said sub-carrier frequency to indicate the distance.
Claim 2
Dependent Claim
163 words
In an optical distance measuring device, a light source, transmitter means for sending a continuous light beam from said source toward a light reflecting object whose distance is to be measured, first means for generating a carrier frequency, second means for frequency modulating said carrier frequency by a sub-carrier frequency, means for simultaneously modulating the intensity of said continuous light beam by said carrier frequency and said subcarrier frequency, receiver means for receiving and detecting the intensity of said light beam from said reflecting object and providing data output signals, means for cross coupling said carrier frequency and sub-carrier frequency from said first and second means to said receiver means, means for determining the relative phase shifts of said carrier frequency and said sub-carrier frequency reflected in the changes in intensity of the outgoing and incoming continuous light beam, and means for combining the determined phase shift of said carrier frequency and the phase shift of said sub-carrier frequency to indicate the distance.
Claim 3
Dependent Claim
90 words
In an optical distance measuring device as claimed in claim 1 including, third means for simultaneously frequency modulating said carrier frequency by a second sub-carrier frequency, said determining means including means for determining the relative phase shifts of said second sub-carrier frequency of the outgoing and incoming light, said cross coupling means cross couples said second sub-carrier frequency, and said combining means includes means for combining the phase shift of said second sub-carrier frequency with the phase shifts of said carrier frequency and said sub-carrier frequency to indicate the distance.
Claim 4
Dependent Claim
60 words
In an optical distance measuring device as claimed in claim 2 in which, said combining means includes a binary digital processing circuit for processing said phase shifts to indicate distance, and said carrier frequency and said first and second sub-carrier frequencies are so spaced in frequency range that said digital prOcessing circuit provides fine, intermediate and course distance measuring accuracies.
Claim 5
Dependent Claim
39 words
In an optical measuring device as claimed in claim 3 in which, said combining means includes means for decoding the output of said binary digital processing circuit to binary code decimal and providing the distance display in decimal numbers.
Claim 6
Dependent Claim
82 words
In an optical distance measuring device as claimed in claim 2 in which, said first and second and third means includes oscillator means for providing an output frequency, second oscillator means being phase and frequency locked to said output frequency for providing said carrier frequency, means for dividing said output frequency into said sub-carrier frequency and said second sub-carrier frequency, and adder means for simultaneously linerally adding said sub-carrier frequency and said second sub-carrier frequency prior to frequency modulating said carrier frequency.
Claim 7
Dependent Claim
82 words
In an optical distance measuring device as claimed in claim 5 in which, said determining means includes third oscillator means simultaneously phase and frequency locked to said output frequency for providing a second output frequency, frequency divider means for dividing said second output frequency into two frequencies, modulator means for modulating said second output frequency with said two frequencies, and mixer means for mixing the output of said modulator means and the carrier frequency and sub-carrier frequencies in said data output signals.
Claim 8
Dependent Claim
37 words
In an optical distance measuring device as claimed in claim 6 in which, said carrier frequency is a given multiple of said sub-carrier frequency, and said sub-carrier frequency is the same multiple of said second sub-carrier frequency.
Claim 9
Dependent Claim
50 words
In an optical distance measuring device as claimed in claim 3 in which, said digital processing circuit includes a binary counter for storing pulses, and gate clock means for providing a group of pulses to said binary counter that correspond in number to the time interval of said phase shifts.
Claim 10
Dependent Claim
43 words
In an optical distance measuring device as claimed in claim 8 including, means for opening said gate clock means to pass a given number of groups of said pulses, and divider means for dividing said pulses of said group by said given number.
Claim 11
Dependent Claim
38 words
In an optical distance measuring device as claimed in claim 8 including, programmer means for gating said gate clock means serially for said phase shifts of said carrier frequency and said sub-carrier frequency and said second sub-carrier frequency.
Claim 12
Dependent Claim
93 words
In an optical distance measuring device as claimed in claim 2 in which, said combining means includes clock gate means for providing groups of pulses having a number of pulses corresponding to the time length of said phase shifts, counter means for counting said pulses, delay portion means for determining that delay portion of said phase shifts resulting from internal circuit delays in said measuring device, said clock gate means translates said delay portion into delay portion pulses, and means for down counting said counter means in response to said delay portion pulses.
Claim 13
Dependent Claim
33 words
In an optical distance measuring device as claimed in claim 11 in which, said delay portion means includes light transmission means for directly cross coupling said outgoing light beam to said receiver means.
Claim 14
Dependent Claim
22 words
In an optical distance measuring device as claimed in claim 12 in which, said light transmission means comprises an optical fiber link.
Claim 15
Dependent Claim
28 words
In an optical distance measuring device as claimed in claim 13 including, means for periodically pivoting said optical fiber link into and out of the light transmission position.
Claim 16
Dependent Claim
30 words
In an optical distance measuring device as claimed in claim 14 including, light attenuating means in said optical fiber link for selectively attenuating the light intensity of the light transmitted.
Claim 17
Dependent Claim
37 words
In an optical distance measuring device as claimed in cLaim 15 including, means for adjusting said light attenuating means to set the intensity of the light transmitted to substantially the light intensity of the reflected light beam.
Claim 18
Dependent Claim
38 words
In an optical distance measuring device as claimed in claim 21 in which, said light source comprises a light emitting diode, and light converting means for translating the light emitted from said diode as a planar light source.
Claim 19
Dependent Claim
25 words
In an optical distance measuring device as claimed in claim 17 in which, said light converting means comprises a relatively short in length light pipe.
Claim 20
Dependent Claim
24 words
In an optical distance measuring device as claimed in claim 17 in which, said light converting means comprises a baffle with a pin hole.
Claim 21
Dependent Claim
34 words
In an optical distance measuring device as claimed in claim 17 in which, said light converting means comprises a baffle with an aperture and a field lens that integrates the light at the aperture.
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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) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |