Radiation detector employing acoustic surface waves

Claim 2

In a radiation detector, the combination of: an acoustic surface wave transmission line including a substrate with a first surface and having first and second acoustic transducers directly mounted on said first surface for transmitting an acoustic surface wave at said first surface from the first transducer to the second transducer with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source operating in the megahertz range to said first transducer; second means for detecting change in phase of the wave received at said second transducer; and means for directing a beam of radiation onto said first surface between said transducers, with the phase change at the surface of said substrate between said transducers being a function of the temperature change at said first surface resulting from incident radiation at said first surface.

Claim 3

A detector as defined in claim 1 wherein said second means includes means for connecting said electrical signal from said first means to said second means as a reference signal.

Claim 4

In a radiation detector, the combination of: an acoustic surface wave transmission line including a substrate with a first surface and having first and second acoustic transducers directly mounted on said first surface for transmitting an acoustic surface wave at said first surface from the first transducer to the second transducer with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source operating in the megahertz range to said first transducer; second means for detecting change in phase of the wave received at said second transducer; means for directing a beam of radiation onto said first surface between said transducers, with the phase change at the surface of said substrate between said transducers being a function of the temperature change at said first surface resulting from incident radiation at said first surface; and a third acoustic transducer mounted on said substrate providing a second acoustic transmission line from said first transducer to said third transducer for use as a reference acoustic signal, with said second means including means for connecting the outputs of said second and third transducers as inputs thereto for comparing the phase of said second and third transducer outputs.

Claim 5

In a radiation detector, the combination of: an acoustic surface wave transmission line including a substrate with a first surface and having first and second acoustic transducers directly mounted on said first surface for transmitting an acoustic surface wave at said first surface from the first transducer to the second transducer with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source operating in the megahertz range to said first transducer; second means for detecting change in phase of the wave received at said second transducer; means for directing a beam of radiation onto said first surface between said transducers, with the phase change at the surface of said substrate between said transducers being a function of the temperature change at said first surface resulting from incident radiation at said first surface; and a third acoustic transducer mounted on said substrate providing a second acoustic transmission line from said first transducer to said third transducer for use as a reference acoustic signal, with said second means including means for connecting the outputs of said second and third transducers as inputs thereto for comparing the phase of said second and third transducer outputs.

Claim 6

A detector as defined in claim 1 wherein said substrate includes a base with a thin film thereon, with the base and film having different phase variation coefficients and thermal properties.

Claim 7

A detector as defined in claim 4 wherein said film has a relatively low phase variation coefficient and a relatively high radiation absorption coefficient with respect to said base.

Claim 8

A detector as defined in claim 1 wherein said substrate is crystal quartz and said first means provides a surface wave of wavelength in the order of 1 to 10 microns.

Claim 9

A detector as defined in claim 1 wherein said transducers are interdigital transducers.

Claim 10

An acoustic temperature detector comprising a plurality of acoustic surface wave transmission lines disposed in a predetermined array, each of said transmission lines including: first and second transducers mounted on a common substrate for transmitting an acoustic surface wave at the surface of the substrate from the first transducer to the second transducer with the intersection of two transmission lines defining a location on said substrate and with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source to said first transducer; and second means for detecting change in phase of the wave received at said second transducer with a change in phase indicating a change in temperature at the surface of the substrate along the path between the first and second means, and with changes in phase along two intersecting paths of the array identifying the location of the temperature change in the substrate.

Claim 11

An acoustic temperature detector comprising a plurality of acoustic surface wave transmission lines disposed in a predetermined array, each of said transmission lines including: first and second transducers mounted on a common substrate for transmitting an acoustic surface wave at the surface of the substrate from the first transducer to the second transducer with the intersection of two transmission lines defining a location on said substrate and with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source to said first transducer; and second means for detecting change in phase of the wave received at said second transducer with a change in phase indicating a change in temperature at the surface of the substrate along the path between the first and second means, and with changes in phase along two intersecting paths of the array identifying the location of the temperature change in the substrate.

Claim 12

In a radiation detector, the combination of: an acoustic surface wave transmission line including a substrate with a first surface and having first and second acoustic transducers directly mounted on said first surface for transmitting an acoustic surface wave at said first surface from the first transducer to the second transducer with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source operating in the megahertz range to said first transducer; second means for detecting change in phase of the wave received at said second transducer, with the phase change at the surface of said substrate between said transducers being a function of the temperature change at said first surface resulting from incident radiation at said first surface; a third acoustic transducer mounted on said substrate providing a second acoustic transmission line from said first transducer to said third transducer for use as a reference acoustic signal, with said second means including means for connecting the outputs of said second and third transducers as inputs thereto for comparing the phase of said second and third transducer outputs; a source of a beam of radiation; means for directing a portion of said beam along a first path to said first surface of said substrate between said first and second transducers; means for directing a portion of said beam along a second path to said first surface of said substrate between said first and third transducer; and means for introducing a sample into one of said paths.

Claim 13

In a radiation detector, the combination of: an acoustic surface wave transmission line including a substrate with a first surface and having first and second acoustic transducers directly mounted on said first surface for transmitting an acoustic surface wave at said first surface from the first transducer to the second transducer with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source operating in the megahertz range to said first transducer; second means for detecting change in phase of the wave received at said second transducer, with the phase change at the surface of said substrate between said transducers being a function of the temperature change at said first surface resulting from incident radiation at said first surface; a third acoustic transducer mounted on said substrate providing a second acoustic transmission line from said first transducer to said third transducer for use as a reference acoustic signal, with said second means including means for connecting the outputs of said second and third transducers as inputs thereto for comparing the phase of said second and third transducer outputs; a source of a beam of radiation; means for directing a portion of said beam along a first path to said first surface of said substrate between said first and second transducers; means for directing a portion of said beam along a second path to said first surface of said substrate between said first and third transducer; and means for introducing a sample into one of said paths.

Claim 14

In a radiation detector, the combination of: an acoustic surface wave transmission line including a substrate with a first surface and having first and second acoustic transducers directly mounted on said first surface for transmitting an acoustic surface wave at said first surface from the first transducer to the second transducer with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source operating in the megahertz range to said first transducer; second means for detecting change in phase of the wave received at said second transducer, with the phase change at the surface of said substrate between said transducers being a function of the temperature change at said first surface resulting from incident radiation at said first surface; said substrate including a base with a thin film thereon, with the base and film having different phase variation coefficients and thermal properties, and with said film having a relatively high phase variation coefficient and a relatively low radiation absorption coefficient with respect to said base.

Claim 15

In a radiation detector, the combination of: an acoustic surface wave transmission line including a substrate with a first surface and having first and second acoustic transducers directly mounted on said first surface for transmitting an acoustic surface wave at said first surface from the first transducer to the second transducer with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source operating in the megahertz range to said first transducer; second means for detecting change in phase of the wave received at said second transducer, with the phase change at the surface of said substrate between said transducers being a function of the temperature change at said first surface resulting from incident radiation at said first surface; said substrate including a base with a thin film thereon, with the base and film having different phase variation coefficients and thermal properties, and with said film having a relatively high phase variation coefficient and a relatively low radiation absorption coefficient with respect to said base.

Claim 16

In a radiation detector, the combination of: an acoustic surface wave transmission line including a substrate with a first surface and having first and second acoustic transducers directly mounted on said first surface for transmitting an acoustic surface wave at said first surface from the first transducer to the second transducer with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source operating in the megahertz range to said first transducer; second means for detecting change in phase of the wave received at said second transducer, with the phase change at the surface of said substrate between said transducers being a function of the temperature change at said first surface resulting from incident radiation at said first surface; said substrate including a base with a thin film thereon, with the base and film having different phase variation coefficients and thermal properties, and said film being cesium iodide and said substrate being crystal quartz.

Claim 17

In a radiation detector, the combination of: an acoustic surface wave transmission line including a substrate with a first surface and having first and second acoustic transducers directly mounted on said first surface for transmitting an acoustic surface wave at said first surface from the first transducer to the second transducer with the penetration of the acoustic wave into the substrate being in the order of the wavelength of the acoustic wave; first means for coupling an electrical signal source operating in the megahertz range to said first transducer; second means for detecting change in phase of the wave received at said second transducer, with the phase change at the surface of said substrate between said transducers being a function of the temperature change at said first surface resulting from incident radiation at said first surface; said substrate including a base with a thin film thereon, with the base and film having different phase variation coefficients and thermal properties, and said film being cesium iodide and said substrate being crystal quartz.