US3832056A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Distance measuring device using electro-optical techniques
Assignee: AGA Corp
•
Filing: 1972-03-13
•
Granted: 1974-08-27
•
Expires: 1992-03-13
Abstract
Abstract An electro-optical surveying instrument for measuring distance utilizing a frequency modulated laser beam is provided with special positioning of lenses so that there is an internal calibration for the lenses utilized so that an exact measurement can be made of a distance from the plumb point of the instrument to the retroreflector at the point from which the distance is being measured. A digital signal level indicator is provided to give the operator of the instrument an exact indication of the strength of the return beam so that he knows exactly whether a reading can be made under a given condition. Electronic logic is provided within the instrument to cancel all second harmonic distortions. The surveying instrument itself is provided with a photo optical switch which allows the instrument to be turned on or off without the need for touching the instrument so as not to in any way affect the exact position of the instrument when a reading is being made. Further, a minimum number of frequencies are utilized to modulate the laser beam while receiving the same range as with instruments utilizing greater numbers of frequencies to modulate the laser.
Inventors
- 👤 J Shipp
- 👤 T Broadbent
- 👤 R Hines
- 👤 W Hollinshead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:57
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/48; G01S7/491; G01S17/00; G01S17/02; G01S17/06; G01S17/08; G01S17/32; G01S17/36
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
268 words
An electro-optical surveying instrument comprising: a. a source of radiation; b. radiation modulating means for modulating said source of radiation at one or more frequencies, c. reference frequency means for supplying a reference frequency signal to said modulating means, to cause said source of radiation to be modulated at said reference frequency, d. radiation sensitive detection means for receiving return radiation signals, e. phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation traveled; f. external optical path means including the total distance modulated radiation travels from said radiation modulating means through said instrument to a target and back through said instrument to said radiation sensitive detection means; g. internal optical path means including the distance modulated radiation traverses from said radiation modulating means through said instrument to said radiation sensitive detection means, h. selective means for selectively measuring said internal or external optical path means, i. said phase comparison means including computing means for computing the formula R E - I + K; where R range to be measured E external path I internal path, and K a constant, said computing means being operative to produce signals corresponding to the range measured, j. display means operative from said computer means for displaying the range measured, said external optical path means and said internal optical path means including a common optical element said instrument having a plumb point from which the range is computed, and said common optical element being positioned relative to said plumb point so as to maintain said constant K equal to zero.
Claim 2
Dependent Claim
268 words
An electro-optical surveying instrument comprising: a. a source of radiation; b. radiation modulating means for modulating said source of radiation at one or more frequencies, c. reference frequency means for supplying a reference frequency signal to said modulating means, to cause said source of radiation to be modulated at said reference frequency, d. radiation sensitive detection means for receiving return radiation signals, e. phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation traveled; f. external optical path means including the total distance modulated radiation travels from said radiation modulating means through said instrument to a target and back through said instrument to said radiation sensitive detection means; g. internal optical path means including the distance modulated radiation traverses from said radiation modulating means through said instrument to said radiation sensitive detection means, h. selective means for selectively measuring said internal or external optical path means, i. said phase comparison means including computing means for computing the formula R E - I + K; where R range to be measured E external path I internal path, and K a constant, said computing means being operative to produce signals corresponding to the range measured, j. display means operative from said computer means for displaying the range measured, said external optical path means and said internal optical path means including a common optical element said instrument having a plumb point from which the range is computed, and said common optical element being positioned relative to said plumb point so as to maintain said constant K equal to zero.
Claim 3
Dependent Claim
59 words
The electro-optical surveying instrument of claim 1 wherein said common optical element include a first beam splitter, said first beam splitter being positioned adjacent said radiation modulating means to transmit radiation to said internal and external path means, the position of said beam splitter relative to said plumb point being operative to control the value of said constant K.
Claim 4
Dependent Claim
192 words
An electro-optical surveying instrument comprising: a. a source of radiation; b. radiation modulating means for modulating said source of radiation at one or more frequencies; c. reference frequency means for supplying a reference frequency signal to said modulating means to cause said source of radiation to be modulated at said reference frequency; d. radiation sensitive detection means for receiving return radiation signals; e. phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation traveled; f. return radiation signal comparator means for comparing, with respect to digital levels, on a sampled basis, individual return radiation signals, g. said phase comparison means including computing means for computing the distance said radiation has traveled; h. said signal comparator being operative to prevent operation of said computing means unless said individual sampled return radiation signals are within predetermined digital levels, said signal comparator means including sampling means for sampling only one of any group, in time, of individual return radiation signals, and display means operative from said computing means for displaying the range measured, said sample signal being operative to control said display means.
Claim 5
Dependent Claim
192 words
An electro-optical surveying instrument comprising: a. a source of radiation; b. radiation modulating means for modulating said source of radiation at one or more frequencies; c. reference frequency means for supplying a reference frequency signal to said modulating means to cause said source of radiation to be modulated at said reference frequency; d. radiation sensitive detection means for receiving return radiation signals; e. phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation traveled; f. return radiation signal comparator means for comparing, with respect to digital levels, on a sampled basis, individual return radiation signals, g. said phase comparison means including computing means for computing the distance said radiation has traveled; h. said signal comparator being operative to prevent operation of said computing means unless said individual sampled return radiation signals are within predetermined digital levels, said signal comparator means including sampling means for sampling only one of any group, in time, of individual return radiation signals, and display means operative from said computing means for displaying the range measured, said sample signal being operative to control said display means.
Claim 6
Dependent Claim
193 words
An electro-optical surveying instrument comprising: a. a source of radiation; b. radiation modulating means for modulating said source of radiation at one or more frequencies; c. reference frequency means for supplying a reference frequency signal to said modulating means to cause said source of radiation to be modulated at said reference frequency; d. radiation sensitive detection means for receiving return radiation signals; e. phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation traveled; f. return radiation comparator means for comparing, with respect to digital levels, on a sampled basis, individual return radiation signals, g. said phase comparison means including computing means for computing the distance said radiation has traveled, h. said signal comparator being operative to prevent operation of said computing means unless said individual sampled return radiation signals are within predetermined digital levels, said signal comparator means including plurality of digital level comparators each responsive to a different digital level of return radiation signal, a plurality of digital display means, respectively responsive to each of said digital level comparators to digitally display the level of a return radiation signal.
Claim 7
Dependent Claim
193 words
An electro-optical surveying instrument comprising: a. a source of radiation; b. radiation modulating means for modulating said source of radiation at one or more frequencies; c. reference frequency means for supplying a reference frequency signal to said modulating means to cause said source of radiation to be modulated at said reference frequency; d. radiation sensitive detection means for receiving return radiation signals; e. phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation traveled; f. return radiation comparator means for comparing, with respect to digital levels, on a sampled basis, individual return radiation signals, g. said phase comparison means including computing means for computing the distance said radiation has traveled, h. said signal comparator being operative to prevent operation of said computing means unless said individual sampled return radiation signals are within predetermined digital levels, said signal comparator means including plurality of digital level comparators each responsive to a different digital level of return radiation signal, a plurality of digital display means, respectively responsive to each of said digital level comparators to digitally display the level of a return radiation signal.
Claim 8
Dependent Claim
39 words
The electro-optical surveying instrument of claim 4 wherein said digital display means are lamps, only one of said lamps being energized at any time in accordance with the highest digital level comparator energized by said individual return radiation signal.
Claim 9
Dependent Claim
13 words
The electro-optical surveying instrument of claim 5 wherein said lamps are neon bulbs.
Claim 10
Dependent Claim
68 words
The electro-optical surveying instrument of claim 4 wherein said signal comparator means samples only one individual return radiation signal out of a group, in time, of individual return radiation signals, said individual digital display means each being energized for a period of time equal to said sample time, in accordance with the digital level of the sampled individual return radiation signal as applied to said digital signal comparators.
Claim 11
Dependent Claim
33 words
The electro-optical surveying instrument of claim 7 including an additional digital display means operative when the return radiation signal is below the lowest level capable of energizing one of said digital comparator means.
Claim 12
Dependent Claim
153 words
An electro-optical surveying instrument comprising: a. A source of radiation; b. Radiation modulating means for modulating said source of radiation at one or more frequencies; c. Reference frequency meaNs for supplying a reference frequency signal to said modulating means to cause said source of radiation to be modulated at said reference frequency; d. Radiation sensitive detection means for receiving return radiation signals; e. Phase comparison means for comparing said reference frequency with the return signal to obtain a measurement of the distance said radiation has traveled; f. said reference frequency means applying, sequencially, different reference frequencies f1, f2, and f3 of different orders of magnitude; g. said phase comparison means obtaining a phase measurement phi with reference frequency f1, phase measurement phi 2 with reference frequency f2 and phase measurement phi 3 with reference frequence f3; h. said phase comparison means including computer means for calculating the Range RA in feet as follows:
Claim 13
Dependent Claim
153 words
An electro-optical surveying instrument comprising: a. A source of radiation; b. Radiation modulating means for modulating said source of radiation at one or more frequencies; c. Reference frequency meaNs for supplying a reference frequency signal to said modulating means to cause said source of radiation to be modulated at said reference frequency; d. Radiation sensitive detection means for receiving return radiation signals; e. Phase comparison means for comparing said reference frequency with the return signal to obtain a measurement of the distance said radiation has traveled; f. said reference frequency means applying, sequencially, different reference frequencies f1, f2, and f3 of different orders of magnitude; g. said phase comparison means obtaining a phase measurement phi with reference frequency f1, phase measurement phi 2 with reference frequency f2 and phase measurement phi 3 with reference frequence f3; h. said phase comparison means including computer means for calculating the Range RA in feet as follows:
Claim 14
Dependent Claim
155 words
An electro-optical surveying instrument comprising: a. A source of radiation; b. radiation modulating means for modulating said source of radiation at one or more frequencies; c. Reference frequency means for supplying a reference frequency signal to said modulating means to cause said source of radiation to be modulated at said reference frequency; d. Radiation sensitive detection means for receiving return radiation signals; e. Phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation has traveled; f. Said reference frequency means applying, sequentially, different reference frequencies f1, f2, and f3 of different orders of magnitude; g. Said phase comparison means obtaining a phase measurement phi 1, with reference frequency f1, phase measurement phi 2 with reference frequency f2 and phase measurement phi 3 with reference frequency f3; h. Said phase comparison means including computer means for calculating the Range RM in meters as follows:
Claim 15
Dependent Claim
155 words
An electro-optical surveying instrument comprising: a. A source of radiation; b. radiation modulating means for modulating said source of radiation at one or more frequencies; c. Reference frequency means for supplying a reference frequency signal to said modulating means to cause said source of radiation to be modulated at said reference frequency; d. Radiation sensitive detection means for receiving return radiation signals; e. Phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation has traveled; f. Said reference frequency means applying, sequentially, different reference frequencies f1, f2, and f3 of different orders of magnitude; g. Said phase comparison means obtaining a phase measurement phi 1, with reference frequency f1, phase measurement phi 2 with reference frequency f2 and phase measurement phi 3 with reference frequency f3; h. Said phase comparison means including computer means for calculating the Range RM in meters as follows:
Claim 16
Dependent Claim
204 words
An electro-optical surveying instrument comprising: a. a source of ranging radiation; b. radiation modulating means for modulating said source of ranging radiation at one or more frequencies; c. reference frequency means for supplying a reference frequency signal to said modulating means to cause said source of ranging radiation to be modulated at said reference frequency; d. radiation sensitive detection means for receiving return ranging radiation signals; e. phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation has traveled; f. electrical power supply means for supplying electrical energy to operate the instrument; and g. initiate means operative to initiate operation of said instrument, said initiate means including a source of light modulated at a high frequency mounted on said instrument, a light sensing means adjacent said light source but out of the path of radiation of said light source and positioned to receive reflected radiation from said light source by means of a reflective Surface positioned adjacent said light source but spaced therefrom, electrical filter means connected to the output of said light sensing means to pass only high frequency signals from said light sensing means to initiate operation of said instrument.
Claim 17
Dependent Claim
204 words
An electro-optical surveying instrument comprising: a. a source of ranging radiation; b. radiation modulating means for modulating said source of ranging radiation at one or more frequencies; c. reference frequency means for supplying a reference frequency signal to said modulating means to cause said source of ranging radiation to be modulated at said reference frequency; d. radiation sensitive detection means for receiving return ranging radiation signals; e. phase comparison means for comparing said reference frequency signal with the return signal to obtain a measurement of the distance said radiation has traveled; f. electrical power supply means for supplying electrical energy to operate the instrument; and g. initiate means operative to initiate operation of said instrument, said initiate means including a source of light modulated at a high frequency mounted on said instrument, a light sensing means adjacent said light source but out of the path of radiation of said light source and positioned to receive reflected radiation from said light source by means of a reflective Surface positioned adjacent said light source but spaced therefrom, electrical filter means connected to the output of said light sensing means to pass only high frequency signals from said light sensing means to initiate operation of said instrument.
Claim 18
Dependent Claim
21 words
The electro-optical surveying instrument of claim 11 wherein said high frequency source of light is energized by said reference frequency means.
Claim 19
Dependent Claim
19 words
The electro-optical surveying instrument of claim 11 wherein said high frequency source of light is a photo emitting diode.
Claim 20
Dependent Claim
17 words
The electro-optical surveying instrument of claim 13 wherein said light sensing means is a photo-sensitive semiconductor device.
Claim 21
Dependent Claim
24 words
The electro-optical surveying instrument of claim 14 wherein said electrical filter means is a capacitor connected to the output of said photosensitive semiconductor device.
Claim 22
Dependent Claim
116 words
A finger operated switch comprising a high frequency radiation source, radiation sensing means, mounting means for mounting said radiation source adjacent said radiation sensing means but out of the path of said radiation source and said sensing means positioned to relfected radiation from said radiation source when a reflective surface is positioned adjacent said radiation source but spaced therefrom; and high frequency electrical filter means connected to the output of said radiation sensing means to pass only high frequency signals from said radiation sensing means to thus provide a signal indicative of the positioning of a reflective surface adjacent said radiation source; said last mentioned signal operative to initiate operation of equipment associated with said switch.
Claim 23
Dependent Claim
116 words
A finger operated switch comprising a high frequency radiation source, radiation sensing means, mounting means for mounting said radiation source adjacent said radiation sensing means but out of the path of said radiation source and said sensing means positioned to relfected radiation from said radiation source when a reflective surface is positioned adjacent said radiation source but spaced therefrom; and high frequency electrical filter means connected to the output of said radiation sensing means to pass only high frequency signals from said radiation sensing means to thus provide a signal indicative of the positioning of a reflective surface adjacent said radiation source; said last mentioned signal operative to initiate operation of equipment associated with said switch.
Claim 24
Dependent Claim
13 words
The switch of claim 16 wherein said radiation source is a photoemitting diode.
Claim 25
Dependent Claim
15 words
The switch of claim 17 wherein said radiation sensing means is a photosensitive semiconductor device.
Claim 26
Dependent Claim
20 words
The switch of claim 18 wherein said high frequency filter means is a capacitor connected to said radiation sensing means.
References Cited (Backward Citations)
US2966090A
Cited
US3365717A
Cited
US3446971A
Cited
US3621268A
Cited
US3619058A
Cited
US3690767A
Cited
US3740141A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-26 | 1978-02-25 | 1978-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-26 | 1982-02-25 | 1982-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-26 | 1986-02-25 | 1986-08-27 | $7700.00 | Window Closed / Lapsed |