Patent EP0474264A2 successfully refreshed from Google Patents.
EP0474264A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Spectrally dispersive imaging Lidar method and apparatus
Assignee: Kaman Aerospace Corp
•
Filing: 1991-11-02
•
Granted: —
•
Expires: 2011-11-02
Abstract
Abstract An imaging UV/visible fluorosensing and Raman lidar system comprises an optical sensor for simultaneously measuring temporally, spatially and spectrally resolved laser backscatter from on the land, on or beneath the surface of bodies of water and in the atmosphere. The present invention utilizes "active" interrogation or "passive" interrogation for remotely and non-destructively probing the spectrally-dependent optical properties of a scene. In the "active" mode, the optical sensor of this invention comprises a transmitter (preferably a tunable solid state laser (10)) which emits pulses of coherent light through a variable or adjustable field-of-view telescope (22) whereupon the light pulses (24) are then propagated towards a scene (26) (e.g., land, sea or atmosphere). Thereafter, laser backscatter (28) is collected by a second variable field-of-view telescope (30) and directed to an imaging system and spectrally dispersive optical subsystem.
Inventors
- 👤 Bobby Lee Ulich
- 👤 Norris R. Keeler
- 👤 Duane Smith
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 20:50
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/28; G01J3/2823; G01J3/44; G01N; G01N21/00; G01N21/62; G01N21/63; G01N21/64; G01N21/65; G01S; G01S17/00; G01S17/02; G01S17/88; G01S17/89; G01S7/00; G01S7/48; G01S7/481; G01S7/4811; G01S7/483; G01S7/484; G01N2021/653; G01N2021/655; G01N21/645; G01N21/6456
Claims Analysis
Total Claims: 63
Claim 1
Independent Claim
148 words
A method for detecting and imaging a target volume enveloped by a backscattering medium which is at least partially transmitting to light characterized by the steps of selectively generating short pulses of light using laser transmitter means; projecting said short pulses of light toward the backscattering medium and at a target volume enveloped by the medium; receiving said pulses of light backscattered from said target volume after a time delay corresponding to the round-trip propagation time of said light pulses to and from said target volume using receiver means; converting said received pulses of light to a video image of said target defining a target volume image, said target volume image having an image intensity pattern associated therewith; and scanning the wavelength of the laser transmitter means to identify the wavelength-dependent differences in said image intensity pattern to thereby improve said video image of said target volume image.
Claim 2
Dependent Claim
26 words
The method as claimed in claim 1 characterized in that said laser transmitter means has an operating wavelength and includes means for tuning said operating wavelength.
Claim 3
Dependent Claim
52 words
The method as claimed in claim 1 or 2 characterized in that said projecting step includes the step of projecting said pulses of light through a first variable field-of-view telescope (22) and said receiving step includes the step of receiving said reflected pulses of light in a second variable field-of-view telescope (30).
Claim 4
Dependent Claim
22 words
The method as claimed in claim 3 characterized by maintaining the field-of-view in each of said first and second telescopes as equal.
Claim 5
Dependent Claim
49 words
The method as claimed in claim 1 or 2 characterized in that said projecting step includes the step of projecting said pulses of light through variable field-of-view telescope means and said receiving step includes the step of receiving said reflected pulses of light from said variable field-of-view telescope means.
Claim 6
Independent Claim
46 words
The method as claimed in anyone of the claims 1 to 5 characterized in that said scanning step is controlled by at least one of the wavelength controlling means selected from the group consisting of harmonic generator means, Raman shifter means and optical parameter oscillator means.
Claim 7
Independent Claim
73 words
A method for remote analysis of a target volume characterized by the steps of generating short pulses of light from laser transmitter means; projecting said generated short pulses of light toward the target volume; detecting said pulses of light backscattered from said target volume after a selected time delay using gated detector means; and spectrally analyzing said detected pulses of light in spectrometer means to create a selected spectra of said target volume.
Claim 8
Dependent Claim
16 words
The method as claimed in claim 7 characterized in that said selected spectra comprises emission spectra.
Claim 9
Dependent Claim
36 words
The method as claimed in claim 8 characterized by selecting the operating wavelength of said laser transmitter means for excitation of fluorescence in said target volume and measuring the emission spectra to analyze said target volume.
Claim 10
Dependent Claim
24 words
The method as claimed in claim 9 characterized in that said emission spectra is analyzed for detection of chemical species in said target volume.
Claim 11
Dependent Claim
16 words
The method as claimed in claim 7 characterized in that said selected spectra comprises excitation spectra.
Claim 12
Dependent Claim
90 words
The method as claimed in claim 7 characterized by the steps of selecting a first operating wavelength of said laser transmitter for excitation of fluorescence in said target volume; measuring a first emission spectra of the excited target volume derived from said first operating wavelength: selecting a second operating wavelength of said laser transmitter for excitation of fluorescence in said target volume; measuring a second emission spectra of the excited target volume derived from said second operating wavelength; comparing said first and second emission spectra to analyze said target volume.
Claim 13
Dependent Claim
33 words
The method as claimed in claim 12 wherein said target volume comprises an oil slick characterized in that said comparing step identifies at least one parameter of the oil in said oil slick.
Claim 14
Dependent Claim
40 words
The method as claimed in claim 7 characterized by calibrating the operating wavelength of said laser transmitter means using laser wavemeter means (18) and comparing an output from said laser wavemeter means (18) with an output from said spectrometer means.
Claim 15
Dependent Claim
17 words
The method as claimed in claim 7 characterized in that said selected spectra comprise Raman scattering spectra.
Claim 16
Dependent Claim
27 words
The method as claimed in claim 15 characterized by passing said detected pulses of light through laser line rejection filter means to improve said Raman scattering spectra.
Claim 17
Dependent Claim
26 words
The method as claimed in claim 16 characterized by positioning said laser line rejection filter either before said gated detector means or before said spectrometer means.
Claim 18
Dependent Claim
51 words
The method as claimed in claim 15 wherein said reflected pulses of light include Raman scattering spectra and spontaneous electronic emission spectra which has larger cross-sections than said Raman scattering spectra and characterized by rejecting said spontaneous electronic emission spectra from said Raman scattering spectra to improve said Raman scattering spectra.
Claim 19
Dependent Claim
24 words
The method as claimed in claim 18 characterized in that said rejecting step is accomplished by selected time delay of said gated detector means.
Claim 20
Dependent Claim
48 words
The method as claimed in claim 19 characterized in that said projecting step includes the step of projecting said pulses of light through a first variable field-of-view telescope and said receiving step includes the step of receiving said reflected pulses of light in a second variable field-of-view telescope.
Claim 21
Dependent Claim
28 words
The method as claimed in claim 19 characterized by adjusting the field-of-view in said first and second telescopes to increase laser power density of said laser transmitter means.
Claim 22
Dependent Claim
47 words
The method as claimed in claim 7 characterized in that said projecting step includes the step of projecting said pulses of light through variable field-of-view telescope means and said receiving step includes the step of receiving said reflected pulses of light from said variable field-of-view telescope means.
Claim 23
Dependent Claim
35 words
The method as claimed in claim 15 characterized by non-linearly optically shifting said laser transmitter means to thereby shorten wavelengths of pulsed light generated by said laser transmitter means thereby improving said Raman scattering spectra.
Claim 24
Dependent Claim
24 words
The method as claimed in claim 20 characterized by narrowing the field-of-view of said second telescope to match the field-of-view of said first telescope.
Claim 25
Dependent Claim
19 words
The method as claimed in claim 7 characterized in that said spectrometer means comprises flat field monolithic spectrometer means.
Claim 26
Dependent Claim
37 words
The method as claimed in claim 7 characterized by anamorphically demagnifying said reflected light pulses to slit shaped light pulses and delivering said slit shaped light pulses to an input slit (52) in said spectrometer means (46).
Claim 27
Dependent Claim
42 words
The method as claimed in claim 7 characterized in that said spectrometer means comprises laser line rejection filter means; diffraction grating means in optical communication with said rejection filter means; and detector array means in optical communication with said diffraction grating means.
Claim 28
Dependent Claim
26 words
The method as claimed in claim 27 characterized by at least one prism pre-disperser means in input optical communication with said laser line rejection filter means.
Claim 29
Dependent Claim
54 words
The method as claimed in claim 7 characterized in that said spectrometer means comprises laser line rejection filter means, at least one prism dispersion means in optical communication with said rejection filter means, intensifier means in optical communication with said prism disperser means and detector array means in optical communication with said intensifier means.
Claim 30
Dependent Claim
58 words
The method as claimed in claim 7 characterized in that the step of spectrally analyzing said detected pulses of light in spectrometer means to create a selected spectra of said target volume is replaced by the step of sweeping the selected time delay of said gated detector means for measuring the temporal luminescence decay of said target volume.
Claim 31
Dependent Claim
14 words
The method as claimed in claim 30 characterized by spatially resolving said temporal decay.
Claim 32
Dependent Claim
14 words
The method as claimed in claim 30 characterized by spectrally resolving said temporal decay.
Claim 33
Dependent Claim
17 words
The method as claimed in claim 30 characterized in that said luminescence temporal decay comprises fluorescence decay.
Claim 34
Dependent Claim
22 words
The method as claimed in claim 33 characterized by spectrally resolving said luminescence temporal decay at at least two different excitation wavelengths.
Claim 35
Dependent Claim
66 words
The method as claimed in claim 32 characterized in that said step of spectrally resolving said temporal decay utilizes an optical system comprising laser line rejection filter means, at least one dispersive prism means in optical communication with said filter means, streak camera tube means in optical communication with said dispersive prism means, and detector array means in optical communication with said streak camera tube means.
Claim 36
Dependent Claim
15 words
The method as claimed in claim 35 characterized by a plurality of dispersive prism means.
Claim 37
Independent Claim
132 words
A method of studying fluid flow field dynamics in a volume enveloped by a backscattering medium which is at least partially transmitting to light characterized by the steps of releasing a fluorescing tracer into a backscattering medium; selectively generating at a first wavelength short pulses of light using laser transmitter means; projecting said short pulses of light toward the backscattering medium and at the tracer enveloped by the medium to thereby excite the tracer; detecting said pulses of light backscattered from said excited tracer at a second wavelength and after a time delay corresponding to the round-trip propagation time of said light pulses to and from the excited tracer using receiver means; and converting said detected pulses of light to a video image of said excited tracer defining an excited tracer image.
Claim 38
Dependent Claim
33 words
The method as claimed in claim 37 characterized by detecting additional excited tracer images by varying the time delay to thereby measure the spatial concentration profiles of the tracer with respect to time.
Claim 39
Dependent Claim
160 words
An apparatus for detecting according to the method of claim 1 and imaging a target volume enveloped by a backscattering medium which is at least partially transmitting to light characterized by laser transmitting means for selectively generating short pulses of light; means for projecting said short pulses of light toward the backscattering medium and at a target volume enveloped by the medium; means for receiving said pulses of light backscattered from said target volume after a time delay corresponding to the round-trip propagation time of said light pulses to and from said target volume using receiver means; means for converting said received pulses of light to a video image of said target defining a target volume image, said target volume image having an image intensity pattern associated therewith; and means for scanning the wavelength of the laser transmitter means to identify the wavelength-dependent differences in said image intensity pattern to thereby improve said video image of said target volume image.
Claim 40
Dependent Claim
26 words
The apparatus as claimed in claim 39 characterized in that said laser transmitter means has an operating wavelength and includes means for tuning said operating wavelength.
Claim 41
Dependent Claim
34 words
The apparatus as claimed in claim 39 characterized in that said means for projecting includes a first variable field-of-view telescope (22) and wherein said means for receiving includes a second variable field-of-view telescope (30).
Claim 42
Dependent Claim
31 words
The apparatus as claimed in claim 39 characterized in that said means for projecting includes variable field-of-view telescope means and wherein said means for receiving includes said variable field-of-view telescope means.
Claim 43
Dependent Claim
45 words
The apparatus as claimed in claim 39 characterized in that said means for scanning is controlled by at least one of the wavelength controlling means selected from the group consisting of harmonic generator means (92), Raman shifter means (94) and optical parameter oscillator means (96)
Claim 44
Dependent Claim
81 words
An apparatus for remote analysis of a target volume according to the method of claim 7, characterized by laser transmitting means for generating short pulses of light; means for projecting said generated short pulses of light toward a target volume; means for detecting said pulses of light backscattered from said target volume after a selected time delay using gated detector means; and spectrometer means for spectrally analyzing said detected pulses of light to create a selected spectra of said target volume.
Claim 45
Dependent Claim
47 words
The apparatus as claimed in claim 44, wherein said selected spectra comprises emission spectra characterized by means for selecting the operating wavelength of said laser transmitter means for excitation of fluorescence in said target volume and means for measuring the emission spectra to analyze said target volume.
Claim 46
Dependent Claim
24 words
The apparatus as claimed in claim 45 characterized by means for analyzing said emission spectra for detection of chemical species in said target volume.
Claim 47
Dependent Claim
104 words
The apparatus as claimed in claim 44 wherein said selected spectra comprises excitation spectra characterized by means for selecting a first operating wavelength of said laser transmitter for excitation of fluorescence in said target volume; means for measuring a first emission spectra of the excited target volume derived from said first operating wavelength; means for selecting a second operating wavelength of said laser transmitter for excitation of fluorescence in said target volume; means for measuring a second emission spectra of the excited target volume derived from said second operating wavelength; means for comparing said first and second emission spectra to analyze said target volume.
Claim 48
Dependent Claim
43 words
The apparatus as claimed in claim 44 characterized by means for calibrating the operating wavelength of said laser transmitter means using laser wavemeter means (18) and comparing an output from said laser wavemeter means (18) with an output from said spectrometer means (46).
Claim 49
Dependent Claim
36 words
The apparatus as claimed in claim 44 wherein said selected spectra comprise Raman scattering spectra characterized by laser line rejection filter means for receiving said detected pulses of light and thereby improving said Raman scattering spectra.
Claim 50
Dependent Claim
30 words
The apparatus as claimed in claim 49 characterized in that said laser line rejection filter is positioned either before said gated detector means (42) or before said spectrometer means (46).
Claim 51
Dependent Claim
34 words
The apparatus as claimed in claim 44 characterized in that said means for projecting includes a first variable field-of-view telescope (20) and wherein said means for receiving includes a second variable field-of-view telescope (22).
Claim 52
Dependent Claim
31 words
The apparatus as claimed in claim 44 characterized in that said means for projecting includes variable field-of-view telescope means and wherein said means for receiving includes said variable field-of-view telescope means.
Claim 53
Dependent Claim
20 words
The apparatus as claimed in claim 44 characterized in that said spectrometer means (46) comprises flat field monolithic spectrometer means.
Claim 54
Dependent Claim
39 words
The apparatus as claimed in claim 44 characterized by means for anamorphically demagnifying said reflected light pulses to slit shaped light pulses and means for delivering said slit shaped light pulses to an input slit in said spectrometer means.
Claim 55
Dependent Claim
48 words
The apparatus as claimed in claim 44 characterized in that said spectrometer means (46) comprises laser line rejection filter means (50); diffraction grating means (56) in optical communication with said rejection filter means (50); and detector array means (60) in optical communication with said diffraction grating means (56).
Claim 56
Dependent Claim
28 words
The apparatus as claimed in claim 55 characterized by at least on prism pre-disperser means (48) in input optical communication with said laser line rejection filter means (50).
Claim 57
Dependent Claim
62 words
The apparatus as claimed in claim 44 characterized in that said spectrometer means (46) comprises laser line rejection filter means (62), at least on prism dispersion means (64) in optical communication with said rejection filter means (62), intensifier means (66) in optical communication with said prism disperser means (64) and detector array means (68) in optical communication with said intensifier means (66).
Claim 58
Dependent Claim
44 words
The apparatus as claimed in claim 44, characterized in that instead of or in addition to the spectrometer means the apparatus includes means for sweeping the selected time delay of said gated detector means for measuring the temporal luminescence decay of said target volume.
Claim 59
Dependent Claim
17 words
The apparatus as claimed in claim 58 characterized by means for spatially resolving (47) said temporal decay.
Claim 60
Dependent Claim
17 words
The apparatus as claimed in claim 58 characterized by means for spectrally resolving (47) said temporal decay.
Claim 61
Dependent Claim
33 words
The apparatus as claimed in claim 60 wherein said luminescence temporal decay comprises fluorescence decay characterized by means for spectrally resolving (47) said luminescence temporal decay at at least two different excitation wavelengths.
Claim 62
Dependent Claim
75 words
The apparatus as claimed in claim 60 characterized in that said means for spectrally resolving said temporal decay utilizes an optical system comprising laser line rejection filter means (70), at least one dispersive prism means (72, 74) in optical communication with said filter means (70), streak camera tube means (76) in optical communication with said dispersive prism means (72, 74) and detector array means (78) in optical communication with said streak camera tube means (76).
Claim 63
Dependent Claim
17 words
The apparatus as claimed in claim 62 characterized by a plurality of dispersive prism means (72, 74).
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.