US3790281A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined system for acoustical-optical microscopy
Assignee: Zenith Electronics LLC
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Filing: 1973-02-26
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Granted: 1974-02-05
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Expires: 1993-02-26
Abstract
Abstract A combined acoustical-optical inspection system, operating at microscopic levels, in which an object to be studied is immersed in water or other sonic fluid propagation medium in close proximity to a partially-metallized semi-reflective mirror formed on an elastically deformable interface surface of a faceplate that engages the sonic propagation medium. The object is insonified with high-frequency acoustic energy, preferably at 100 MHz or more, from the side opposite the interface surface, producing a ripple pattern on the interface surface representative of the acoustic properties of the object. The object is scanned with a laser beam, through the interface; a reflected fraction of the beam is utilized to develop an acoustic image of the object and a transmitted fraction of the beam is employed to develop a precisely correlated optical image of the object. The two images may be superimposed for interpretation purposes.
Inventors
- 👤 L Kessler
- 👤 A Korpel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:44
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/04; G01N29/06; G01N29/0609; G01N29/0654; G01N29/0681; Y; Y10; Y10S; Y10S359/00; Y10S359/901
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
234 words
A comparative inspection system for correlated acoustical and optical examination of an object, comprising: support means for supporting an object in engagement with a fluid sonic propagation medium; boundary means defining an elastically deformable partially light-reflective interface surface disposed adjacent to the object and coupled to the object by the medium, the boundary means reacting to acoustic vibration of the object to generate on the interface surface a ripple pattern characteristic of the object; insonification means for insonifying the object with high frequency acoustic energy; optical scanning means, including illumination means for developing a high-energy light beam of small diameter and deflection means for deflecting that beam across the interface, a first fraction of the beam being reflected from the ripple pattern on the interface surface, angularly modulated in accordance with the acoustical properties of the object, and a second fraction of the beam being transmitted through the object, amplitude modulated in accordance with the optical properties of the object; first photodetection means for receiving the reflected fraction of the beam and developing a first electrical signal representative of an acoustical image of the object; second photodetection means for receiving the transmitted fraction of the beam and developing a second electrical signal representative of an optical image of the object; and imaging means utilizing the first and second electrical signals to generate correlated visual representations of the acoustical and optical images of the object.
Claim 2
Dependent Claim
234 words
A comparative inspection system for correlated acoustical and optical examination of an object, comprising: support means for supporting an object in engagement with a fluid sonic propagation medium; boundary means defining an elastically deformable partially light-reflective interface surface disposed adjacent to the object and coupled to the object by the medium, the boundary means reacting to acoustic vibration of the object to generate on the interface surface a ripple pattern characteristic of the object; insonification means for insonifying the object with high frequency acoustic energy; optical scanning means, including illumination means for developing a high-energy light beam of small diameter and deflection means for deflecting that beam across the interface, a first fraction of the beam being reflected from the ripple pattern on the interface surface, angularly modulated in accordance with the acoustical properties of the object, and a second fraction of the beam being transmitted through the object, amplitude modulated in accordance with the optical properties of the object; first photodetection means for receiving the reflected fraction of the beam and developing a first electrical signal representative of an acoustical image of the object; second photodetection means for receiving the transmitted fraction of the beam and developing a second electrical signal representative of an optical image of the object; and imaging means utilizing the first and second electrical signals to generate correlated visual representations of the acoustical and optical images of the object.
Claim 3
Dependent Claim
35 words
A comparative acoustical-optical inspection system, according to claim 1, in which said illumination means comprises a laser which develops a phase-coherent light beam having a diameter, at the interface, of no more than 10 microns.
Claim 4
Dependent Claim
48 words
A comparative acoustical-optical inspection system, according to claim 1, in which the imaging means comprises an oscilloscopic display and means for applying both the first and second electrical signals to the display effectively to generate a composite image comprising superimposed simultaneous acoustical and optical images of the object.
Claim 5
Dependent Claim
39 words
A comparative acoustical-optical inspection system, according to claim 3, in which the display is a two-color display, and in which the acoustical image is presented in a first color and the optical image is presented in a second color.
Claim 6
Dependent Claim
50 words
A comparative acoustical-optical inspection system, according to claim 1, in which the imaging means comprises at least one oscilloscopic display, and further comprising deflection control means, coupled to both the optical scanning deflection means and to the display, for synchronizing scanning in the display with optical scanning of the object.
Claim 7
Dependent Claim
71 words
A comparative acoustical-optical inspection system, according to claim 1, in which the support means comprises a transparent base member having an acoustical impedance substantially greater tHan the acoustical impedance substantially greater than the acoustical impedance of the sonic propagation medium, upon which the object is supported, and in which the boundary means comprises a faceplate member having an acoustical impedance approximately matched to the acoustical impedance of the sonic propagation medium.
Claim 8
Dependent Claim
19 words
A comparative acoustical-optical inspection system, according to claim 6, in which the base member is formed of fused quartz.
Claim 9
Dependent Claim
41 words
A comparative acoustical-optical inspection system, according to claim 6, in which the faceplate member is formed of a transparent resin having an interface surface engaging the sonic propagation medium, and having a thin, partially transparent metallic coating on its interface surface.
Claim 10
Dependent Claim
35 words
A comparative acoustical-optical inspection system according to claim 8, in which the sonic propagation medium is water and the resin for the faceplate member is selected from the group consisting of polymethylmethacrylate and polycarbonate resins.
Claim 11
Dependent Claim
53 words
A comparative acoustical-optical inspection system, according to claim 1, in which the insonification means includes oscillator means, generating an electrical oscillation signal at a given frequency of at least 100 MHz, and electro-acoustic transducer means, coupled to the oscillator means and to the support means, for insonifying the object at said given frequency.
Claim 12
Dependent Claim
59 words
A comparative acoustical-optical inspection system, according to claim 10, in which the first photodetection means includes a photosensitive optical-electrical transducer positioned to intercept the reflected fraction of the light beam, and an amplitude detector coupled to the optical-electrical transducer, for generating an amplitude-modulated first electrical signal corresponding to the angular modulation of the reflected fraction of the light beam.
Claim 13
Dependent Claim
90 words
A comparative acoustical-optical inspection system, according to claim 10, in which the first photodetection means includes a photosensitive optical-electrical transducer positioned to intercept the reflected fraction of the light beam, and a phase detector, coupled to the optical-electrical transducer and to the oscillator, for generating an amplitude-modulated first electrical signal representative of angular modulation of the reflected fraction of the beam and of phase variations in the reflected fraction of the beam relative to the oscillator output signal, whereby the acoustical image developed by the imaging means is a hologram.
Claim 14
Independent Claim
140 words
The method of combined acoustical-optical microscopy comprising the steps of: immersing an object within a fluid sonic preparation medium in close proximity to an elastically deformable partially light-reflective interface surface that reflects and transmits predetermined fractions of an impinging light beam, the sonic propagation medium contacting the interface surface; scanning the object, through the interface surface, with a high energy light beam having a diameter of the order of ten microns or less; insonifying the object, at a frequency of at least 100 MHz, to create a ripple pattern at the interface surface which is characteristic of the acoustic properties of the object, the ripple pattern angularly modulating the reflected fraction of the beam; detecting the reflected and transmitted fractions of the beam; and developing, from the detected beam fractions, inherently correlated simultaneous acoustical and optical images of the object.
Claim 15
Independent Claim
140 words
The method of combined acoustical-optical microscopy comprising the steps of: immersing an object within a fluid sonic preparation medium in close proximity to an elastically deformable partially light-reflective interface surface that reflects and transmits predetermined fractions of an impinging light beam, the sonic propagation medium contacting the interface surface; scanning the object, through the interface surface, with a high energy light beam having a diameter of the order of ten microns or less; insonifying the object, at a frequency of at least 100 MHz, to create a ripple pattern at the interface surface which is characteristic of the acoustic properties of the object, the ripple pattern angularly modulating the reflected fraction of the beam; detecting the reflected and transmitted fractions of the beam; and developing, from the detected beam fractions, inherently correlated simultaneous acoustical and optical images of the object.
Claim 16
Dependent Claim
47 words
The method of combined acoustical-optical microscopy, according to claim 13, in which image development is effected by means of at least one oscilloscopic image reproducer, and comprising the further step of scanning the image reproducer of in direct synchronism with the light beam scansion of the object.
Claim 17
Dependent Claim
26 words
The method of combined acoustical-optical microscopy, according to claim 13, in which insonification is effected at an acute angle to the normal to the interface surface.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |