US3886331A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic scanning spectrophotometer system
Assignee: Tektronix Inc
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Filing: 1973-09-14
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Granted: 1975-05-27
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Expires: 1993-09-14
Abstract
Abstract A spectrophotometer system is described in which the optical spectrum of an input light signal is linearly dispersed as a function of wavelength and the spectral image of a portion thereof is scanned electronically or mechanically to cause a photoelectric detector to produce an electrical analog output signal having spectral regions of different amplitudes corresponding to the intensity of the spectral image. The analog output signal is transmitted through a normalizer circuit for modulating by different predetermined amounts the amplitudes of such spectral regions to provide a normalized analog output signal which is compensated for the nonuniform wavelength response characteristics of the system. The detector may be an image detector in the form of a photosensitive semiconductor diode array which is scanned by electronic switching, or by an electron beam such as when the array is used as the target of an image tube. The normalizer circuit includes a function generator whose output is connected to one input of a multiplier circuit having its other input connected to the output of the detector to produce the normalized spectral signal at the output of such multiplier. The input of the function generator is a ramp voltage signal which starts at the beginning of the scan and may also be connected to the horizontal deflection plates of a cathode ray tube display device having the normalized spectral signal applied to its vertical deflection plates. An intensified marker spot is moved along the spectral signal waveform displayed on the screen of the cathode ray tube to indicate different wavelength portions and to provide a reference for expanding a portion of the display. A readout is provided on such screen of the wavelength and intensity power of the indicated wavelength portion after measurement by digital voltmeters.
Inventors
- 👤 Jr Joseph Philip Schierer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 16:36
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/28; G01J3/2803
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
191 words
A spectrophotometer apparatus in which the improvement comprises: optical means for separating an input light signal into spacially displaced spectral images of light of different wavelengths and intensities; photoelectric detector means for receiving and measuring said spectral images; scanning means for scanning said spectral images to cause said detector means to produce an electrical analog output signal including spectral intervals having time and amplitude characteristics corresponding to the wavelength and intensity of said spectral images, said scanning means also producing an electrical analog control signal during said scanning; and electronic normalizer means connected to the output of said detector means, including function generator means for changing by different predetermined amounts the amplitudes of the spectral intervals of said analog output signal in response to a predetermined electrical output signal produced by said function generator means when the analog control signal is applied to the input of said function generator means by said scanning means, to compensate for nonuniform spectral response characteristics of said apparatus and to produce a normalized analog output signal whose spectral intervals have amplitudes proportional to the intensities of the corresponding spectral images of the input light signal.
Claim 2
Dependent Claim
191 words
A spectrophotometer apparatus in which the improvement comprises: optical means for separating an input light signal into spacially displaced spectral images of light of different wavelengths and intensities; photoelectric detector means for receiving and measuring said spectral images; scanning means for scanning said spectral images to cause said detector means to produce an electrical analog output signal including spectral intervals having time and amplitude characteristics corresponding to the wavelength and intensity of said spectral images, said scanning means also producing an electrical analog control signal during said scanning; and electronic normalizer means connected to the output of said detector means, including function generator means for changing by different predetermined amounts the amplitudes of the spectral intervals of said analog output signal in response to a predetermined electrical output signal produced by said function generator means when the analog control signal is applied to the input of said function generator means by said scanning means, to compensate for nonuniform spectral response characteristics of said apparatus and to produce a normalized analog output signal whose spectral intervals have amplitudes proportional to the intensities of the corresponding spectral images of the input light signal.
Claim 3
Dependent Claim
21 words
Apparatus in accorDance with claim 1 in which the scanning means is an electronic scanning means for scanning the detector means.
Claim 4
Dependent Claim
33 words
Apparatus in accordance with claim 2 which also includes a display means for providing a visual display of said normalized analog output signal, said display means being synchronized to said electronic scanning means.
Claim 5
Dependent Claim
75 words
Apparatus in accordance with claim 3 in which the detector means is an image tube having a photosensitive target, the display means is a cathode ray tube and the scanning signal generator means includes a ramp voltage generator means for applying a horizontal scan signal to horizontal deflection means in both the image tube and a cathode ray tube, said normalized output signal being applied to the vertical deflection means of said cathode ray tube.
Claim 6
Dependent Claim
39 words
Apparatus in accordance with claim 4 in which the image tube has a vertical deflection means connected to the output of an oscillator producing a vertical scan signal of high frequency many times that of said horizontal scan signal.
Claim 7
Dependent Claim
56 words
Apparatus in accordance with claim 3 in which the display means includes a cathode ray tube having a phosphor screen which produces a light image display of the waveform of said normalized signal, and pointer means for producing a pointer spot on said phosphor screen which is movable along said waveform to different selected spectral intervals.
Claim 8
Dependent Claim
22 words
Apparatus in accordance with claim 6 in which the pointer spot is an intensified spot of greater brightness than the waveform display.
Claim 9
Dependent Claim
15 words
Apparatus in accordance with claim 6 in which the pointer spot is a circular ring.
Claim 10
Dependent Claim
59 words
Apparatus in accordance with claim 6 in which the display means also includes an expander means for changing the slope of a horizontal ram signal applied to the horizontal deflection means of the cathode ray tube to expand the horizontal axis without expanding the verticle axis of a selected portion of the signal display indicated by the pointer spot.
Claim 11
Dependent Claim
41 words
Apparatus in accordance with claim 6 in which the display means includes a readout means for producing a readout display on said phosphor screen of the wavelength of the selected spectral interval of the signal display indicated by the pointer spot.
Claim 12
Dependent Claim
37 words
Apparatus in accordance with claim 6 in which the display means includes a readout means for producing a readout display or said phosphor screen of the intensity of the selected spectral interval indicated by the pointer spot.
Claim 13
Dependent Claim
16 words
Apparatus in accordance with claim 2 in which the detector means is a photosensitive image detector.
Claim 14
Dependent Claim
38 words
Apparatus in accordance with claim 12 in which the detector is an image tube having a photosensitive target and an electron beam deflection means for scanning said target connected to the output of a scanning signal generator means.
Claim 15
Dependent Claim
38 words
Apparatus in accordance with claim 12 in which the image detector is a semiconductor photosensitive diode array and the scanning means includes electronic switch means for selectively switching the diodes of said array to scan the detected images.
Claim 16
Dependent Claim
22 words
Apparatus in accordance with claim 12 in which the image detector is an image tube having a semiconductor diode mosaic photosensitive target.
Claim 17
Dependent Claim
51 words
Apparatus in accordance with claim 1 in which the optical means includes a movable slit member having a plurality of light transparent slits of different width which are selectively moved into the path of the input light signal transmitted to the detector means to determine the width of the spectral image.
Claim 18
Dependent Claim
44 words
Apparatus in accordance with claim 16 in which the slit member includes a light transparent support plate having a light opaque coating on one side of said support plate, said coating being provided with a plurality of spaced openings therethrough to form said slits.
Claim 19
Dependent Claim
58 words
Apparatus in accordance with claim 1 in which the normalizer means includes a multiplier circuit having one input connected to the output of the detector means and another input connected to the output of the function generatOr whose input is connected to a ramp signal generator, said function generator being programmable to provide different predetermined function output signals.
Claim 20
Dependent Claim
56 words
Apparatus in accordance with claim 18 in which the ramp signal generator applies a ramp signal to the scanning means for scanning the detector means and applies a corresponding ramp control signal to the function generator for producing a function output signal which is multiplied with the detector output signal to produce said normalized output signal.
Claim 21
Dependent Claim
91 words
Apparatus in accordance with claim 19 in which the optical means includes a movable diffraction grating and an associated control means for moving the grating and producing a D.C. offset signal correspoinding to the position of said grating, and the normalizer means includes an adder circuit having one input connected to the output of the control means and another input connected to the ramp signal generator for adding the offset signal to the ramp signal to produce a combined signal which is applied as the control signal to the function generator.
Claim 22
Dependent Claim
142 words
A spectrophotometer apparatus in which the improvement comprises: optical means for separating an input light signal into spectral images of light of different wavelengths; photoelectric detector means for receiving and measuring said spectral images, said detector means including a photosensitive charge image tube having a PN semiconductor diode mosaic photosensitive target and an electron beam deflection means; electronic scanning means for applying a scanning signal to said deflection means to scan said electron beam across said target to produce on an output terminal of said tube an electrical output signal including spaced spectral intervals corresponding to the spectral images detected by said target; and electronic normalizer means connected to the output of said detector means for changing by different predetermined amounts the amplitudes of the spectral intervals of said output signal in response to a control signal corresponding to the scanning signal.
Claim 23
Dependent Claim
142 words
A spectrophotometer apparatus in which the improvement comprises: optical means for separating an input light signal into spectral images of light of different wavelengths; photoelectric detector means for receiving and measuring said spectral images, said detector means including a photosensitive charge image tube having a PN semiconductor diode mosaic photosensitive target and an electron beam deflection means; electronic scanning means for applying a scanning signal to said deflection means to scan said electron beam across said target to produce on an output terminal of said tube an electrical output signal including spaced spectral intervals corresponding to the spectral images detected by said target; and electronic normalizer means connected to the output of said detector means for changing by different predetermined amounts the amplitudes of the spectral intervals of said output signal in response to a control signal corresponding to the scanning signal.
References Cited (Backward Citations)
US2414486A
Cited
US3011391A
Cited
US3369447A
Cited
US3561872A
Cited
US3508813A
Cited
US3547542A
Cited
US3496404A
Cited
US3646331A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |