US3867628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulsed light receiver and method
Assignee: Scientific Technology Inc
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Filing: 1973-07-30
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Granted: 1975-02-18
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Expires: 1993-07-30
Abstract
Abstract A receiver for pulsed light having a sensing means providing an electrical output responsive to said light. Means are provided for additionally controlling the electrical output to a point of optimum light sensitivity through application of an electrical input. Optimum sensitivity is set at a constant level in the absence of light input by said electrical input. Means are provided for rejecting the effects of light inputs on the electrical output for pulse frequencies contained in received light pulses which are below a predetermined frequency and for accepting pulse frequencies contained in received light pulses which are above said predetermined frequency.
Inventors
- 👤 Roger M Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:40
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/22; G01F23/28; G01F23/284; G01F23/292; G01F23/2921; G01F23/2928; G06; G06M; G06M1/00; G06M1/08; G06M1/10; G06M1/101; H; H03; H03K; H03K5/00; H03K5/156
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
123 words
A receiver comprising means for producing an electrical output responsive to electromagnetic radiation input, an electrical control input terminal connected to said means producing electrical output, means connected to said electrical control input terminal for controlling said electrical output at a constant level in the absence of electromagnetic radiation input so that said means responsive to electromagnetic radiation is operated at optimum sensitivity, means for attenuating electrical output due to ambient electromagnetic radiation pulse frequency components below a predetermined pulse frequency component connected to said electrical control input terminal, and means for providing a low load impedance for said electrical output above said predetermined pulse frequency component so that the fastest response time of said means responsive to electromagnetic radiation may be utilized.
Claim 2
Dependent Claim
123 words
A receiver comprising means for producing an electrical output responsive to electromagnetic radiation input, an electrical control input terminal connected to said means producing electrical output, means connected to said electrical control input terminal for controlling said electrical output at a constant level in the absence of electromagnetic radiation input so that said means responsive to electromagnetic radiation is operated at optimum sensitivity, means for attenuating electrical output due to ambient electromagnetic radiation pulse frequency components below a predetermined pulse frequency component connected to said electrical control input terminal, and means for providing a low load impedance for said electrical output above said predetermined pulse frequency component so that the fastest response time of said means responsive to electromagnetic radiation may be utilized.
Claim 3
Dependent Claim
29 words
A receiver for receiving light pulses as in claim 1 wherein said means responsive to electromagnetic radiation comprises a phototransistor having a collector, an emitter and a base connection.
Claim 4
Dependent Claim
35 words
A receiver for receiving light pulses as in claim 2 wherein said means for controlling said electrical output comprises a constant current source connected to said base presenting a high impedance to said base connection.
Claim 5
Dependent Claim
26 words
A receiver for receiving light pulses as in claim 2 wherein said means for controlling said electrical output comprises a high resistance connected to said base.
Claim 6
Dependent Claim
32 words
A receiver for receiving light pulses as in claim 2 wherein said means for attenuating comprises feedback means between said emitter and said base connections whereby photo-transistor emitter-collector current controls base-emitter current.
Claim 7
Dependent Claim
37 words
A receiver for receiving light pulses as in claim 5 together with low pass filter means in parallel with said feedback means for shunting said means for attenuating pulse frequency components above said predetermined pulse frequency component.
Claim 8
Dependent Claim
90 words
A receiver for receiving light pulses as in claim 2 wherein said electrical control input terminal comprises said photo-transistor base and wherein said means for attenuating comprises a resistor connected to said photo-transistor emitter, and a transistor having base, collector and emitter terminals connected so that said transistor collector-emitter circuit is connected to said photo-transistor base and said transistor base is connected to said photo-transistor emitter, whereby photo-transistor emitter-collector current through said resistor serves to cause said transistor collector-emitter circuit to conduct a predetermined portion of said photo-transistor base current.
Claim 9
Dependent Claim
43 words
A receiver for receiving light pulses as in claim 7 together with a capacitor connected in parallel with said resistor providing a shunt path for by-passing said transistor base for said electrical output frequency components which are above said predetermined pulse frequency component.
Claim 10
Dependent Claim
34 words
A receiver for receiving light pulses as in claim 1 wherein said means for providing a low load impedance includes means for additional attenuation of ambient electromagnetic radiation inputs below said predetermined pulse frequency.
Claim 11
Dependent Claim
32 words
A receiver for receiving light pulses as in claim 9 wherein said means for additional attenuation is a capacitor coupling said output to an amplifier configured as a current to voltage converter.
Claim 12
Dependent Claim
25 words
A receiver for receiving light pulses as in claim 1 wherein said low load impedance comprises an amplifier configured as a current to voltage converter.
Claim 13
Dependent Claim
42 words
A receiver for receiving light pulses as in claim 11 together with a capacitor coupling said electrical output to said amplifier, said capacitor operating to provide additional attenuation of electrical output due to ambient electromagnetic radiation inputs below said predetermined pulse frequency.
Claim 14
Dependent Claim
39 words
A receiver for receiving light pulses as in claim 1 together with a case for containing the receiver, said case providing radiated interference shielding therefor and having an opening in one wall for allowing the pulsed light to pass.
Claim 15
Dependent Claim
103 words
A receiver for receiving light pulses as in claim 13 including, means for producing electromagnetic radiation pulses at a predetermined repetition rate, and pulses containing pulse frequency components above said predetermined frequency, and means for producing pulses adapted to be energized by an energy source, said pulses having a narrow width relative to said pulse repetition rate, whereby said pulses may attain a higher peak radiated energy output at a lower power dissipation thereby providing a greater range from the receiver at which an object may be positioned to reflect said pulses for reception and sensing by said means responsive to electromagnetic radiation.
Claim 16
Dependent Claim
68 words
A receiver for receiving light pulses as in claim 14 wherein said means for producing electromagnetic radiation pulses is a pulse modulator and said predetermined pulse repetition rate is higher for discrimination necessary when the object is within the receiver field for a short time, and said pulse repetition rate may be lower for adequate discrimination when the object is within the receiver field for a longer time.
Claim 17
Dependent Claim
56 words
A receiver for receiving light pulses as in claim 14 together with means for blocking direct transmission of electromagnetic radiation pulses from said means for producing pulses to said light sensitive means, and optical means positioned in said opening for passing said pulses and for further attenuation of some wave lengths in said ambient electromagnetic radiation.
Claim 18
Dependent Claim
24 words
A receiver for receiving light pulses as in claim 16 together with means for sealing said case for preventing the presence of internal moisture.
Claim 19
Dependent Claim
34 words
A receiver for receiving light pulses as in claim 13 together with optical means positioned in said opening for passing said pulses and for further attenuation of a part of said ambient electromagnetic radiation.
Claim 20
Dependent Claim
24 words
A receiver for receiving light pulses as in claim 18 together with means for sealing said case for preventing the presence of internal moisture.
Claim 21
Independent Claim
115 words
A method of receiving light pulse frequency components above a predetermined pulse component frequency utilizing an electromagnetic radiation sensor having an electrical control comprising the steps of biasing the sensor to produce a constant output substantially at the optimum radiation sensitivity in the absence of electromagnetic radiation, attenuating sensor output due to ambient electromagnetic radiation pulse frequency components below the predetermined pulse component frequency by negatively feeding back the electrical output resulting therefrom to the electrical control of the sensor, filtering the feedback to prevent feedback signals above the predetermined pulse component frequency, and presenting a high impedance to the electrical control of the sensor to maintain the sensor at the optimum radiation sensitivity point.
Claim 22
Independent Claim
115 words
A method of receiving light pulse frequency components above a predetermined pulse component frequency utilizing an electromagnetic radiation sensor having an electrical control comprising the steps of biasing the sensor to produce a constant output substantially at the optimum radiation sensitivity in the absence of electromagnetic radiation, attenuating sensor output due to ambient electromagnetic radiation pulse frequency components below the predetermined pulse component frequency by negatively feeding back the electrical output resulting therefrom to the electrical control of the sensor, filtering the feedback to prevent feedback signals above the predetermined pulse component frequency, and presenting a high impedance to the electrical control of the sensor to maintain the sensor at the optimum radiation sensitivity point.
Claim 23
Dependent Claim
50 words
A method of receiving light pulses as in claim 20 together with the steps of presenting a low load impedance to the output of the sensor to obtain the fastest sensor response time and configuring the load impedance to further reject ambient electromagnetic radiation below the predetermined pulse coMponent frequency.
Claim 24
Dependent Claim
31 words
A method of receiving light pulses as in claim 21 together with the step of absorbing a part of the ambient electromagnetic radiation while simultaneously allowing the pulsed light to pass.
Claim 25
Dependent Claim
33 words
A method of receiving light pulses as in claim 22 together with the step of sealing the sensor from the atmosphere to prevent condensed moisture from collecting internally and blocking the pulsed light.
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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) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |