Patent US2879026A successfully refreshed from Google Patents.
EP0079751A1
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Noise erasing method for stimulable phosphor sheet
Assignee: Fujifilm Holdings Corp
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Filing: 1982-11-09
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Granted: —
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Expires: 2002-11-09
Abstract
Abstract In a radiation image recording and read-out system in which a stimulable phosphor sheet (4) is repeatedly used for recording radiation images and noise due to residual radiation energy on the phosphor sheet (4) is eliminated by exposing the phosphor sheet (4) to erasing light (11) prior to the recording of a radiation image thereon, the level of residual radiation energy is determined and the amount of exposure of the phosphor sheet (4) to the erasing light (11) is controlled according to the determined level of residual radiation energy. The exposure amount is controlled to erase residual radiation energy to a level within the range between 0.01 and 0.0001 with the maximum of the originally stored radiation energy taken as 100.
Inventors
- 👤 Toshiaki Suzuki
- 👤 Kazuo Horikawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 21:55
CPC Classifications
G; G03; G03B; G03B42/00; G03B42/02; G01; G01T; G01T1/00; G01T1/16; G01T1/20; G01T1/2012; G01T1/2016; G03C; G03C5/00; G03C5/16; G21; G21K; G21K4/00
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
102 words
A method for erasing noise from a stimulable phosphor sheet capable of being repeatedly used for radiation image recording and read-out, in which development of noise at the time of read-out of the radiation image from said stimulable phosphor sheet is eliminated by exposing said stimulable phosphor sheet to light prior to the recording of the radiation image thereon,characterized in that the method comprises the steps of: determining the level of residual radiation energy remaining on said stimulable phosphor sheet, and controlling the exposure amount of said stimulable phosphor sheet to said light according to the determined level of residual radiation energy.
Claim 2
Independent Claim
102 words
A method for erasing noise from a stimulable phosphor sheet capable of being repeatedly used for radiation image recording and read-out, in which development of noise at the time of read-out of the radiation image from said stimulable phosphor sheet is eliminated by exposing said stimulable phosphor sheet to light prior to the recording of the radiation image thereon,characterized in that the method comprises the steps of: determining the level of residual radiation energy remaining on said stimulable phosphor sheet, and controlling the exposure amount of said stimulable phosphor sheet to said light according to the determined level of residual radiation energy.
Claim 3
Dependent Claim
40 words
A method as claimed in claim 1 wherein said exposure amount is controlled to erase residual radiation energy to a level within the range between 0.01 and 0.0001 with the maximum of the originally stored radiation energy taken as 100.
Claim 4
Independent Claim
50 words
A method as claimed in either of claims 1 and 2 wherein the level of residual radiation energy is determined on the basis of the electric image signal read out from said stimulable phosphor sheet at the read-out step conducted for obtaining a visual image for viewing and diagnostic purposes.
Claim 5
Independent Claim
45 words
A method as claimed in either of claims 1 and 2 wherein the level of residual radiation enerqy is determined on the basis of the recording information obtained by a preliminary read-out step which is conducted to investigate the recording information for determining read-out conditions.
Claim 6
Independent Claim
45 words
A method as claimed in either of claims 1 and 2 wherein the level of residual radiation energy is determined by detecting light instantaneously emitted from said stimulable phosphor sheet when said stimulable phosphor sheet is exposed to radiation to record a radiation image thereon.
Claim 7
Independent Claim
89 words
An apparatus for erasing noise from a stimulable phosphor sheet capable of being repeatedly used for radiation image recording and read-out, which apparatus comprises a means for exposing said stimulable phosphor sheet to light in order to erase noise prior to the recording of a radiation image thereon, a means for determining the level of residual radiation energy remaining on said stimulable phosphor sheet, and a means for controlling the exposure amount of said stimulable phosphor sheet to said light according to the determined level of residual radiation energy.
Claim 8
Independent Claim
89 words
An apparatus for erasing noise from a stimulable phosphor sheet capable of being repeatedly used for radiation image recording and read-out, which apparatus comprises a means for exposing said stimulable phosphor sheet to light in order to erase noise prior to the recording of a radiation image thereon, a means for determining the level of residual radiation energy remaining on said stimulable phosphor sheet, and a means for controlling the exposure amount of said stimulable phosphor sheet to said light according to the determined level of residual radiation energy.
Claim 9
Dependent Claim
41 words
An apparatus as claimed in claim 6 wherein said means for determining the level of residual radiation energy is a means for detecting a value corresponding to the residual radiation energy level from an output of a radiation image read-out means.
Claim 10
Dependent Claim
50 words
An apparatus as claimed in claim 6 wherein said means for determining the level of residual radiation energy is a means for detecting a value corresponding to the residual radiation energy level from an output obtained by a preliminary read-out conducted to investigate the recording information for determining read-out conditions.
Claim 11
Independent Claim
36 words
An apparatus as claimed in any one of claims 6 to 8 wherein said means for determining the level of residual radiation energy comprises a means for scanning said stimulable phoshor sheet with a laser beam.
Claim 12
Independent Claim
43 words
An apparatus as claimed in any one of claims 6 to 8 wherein said means for determining the level of residual radiation energy comprises a light source capable of emitting light to the whole surface of said stimulable phosphor sheet at a time.
Claim 13
Dependent Claim
57 words
An apparatus as claimed in claim 6 wherein said means for determining the level of residual radiation energy is a light source capable of emitting light to the whole surface of said stimulable phosphor sheet at a time and also serves as said means for exposing said stimulable phosphor sheet to light in order to erase noise.
Claim 14
Independent Claim
46 words
An apparatus as claimed in any one of claims 6 to 11 wherein said means for controlling the exposure amount comprises a power controller for controlling the electric power applied to said means for exposing said stimulable phosphor sheet to light in order to erase noise.
Claim 15
Independent Claim
46 words
An apparatus as claimed in any one of claims 6 to 11 wherein said means for controlling the exposure amount comprises a timer for timing the turning on and off of said means for exposing said stimulable phosphor sheet to light in order to erase noise.
Claim 16
Independent Claim
50 words
An apparatus as claimed in any one of claims 6 to 11 wherein said means for controlling the exposure amount comprises at least one comparator and at least one switch for turning on and off said means for exposing said stimulable phosphor sheet to light in order to erase noise.
Claim 17
Independent Claim
51 words
An apparatus as claimed in any one of claims 6 to 14 wherein said means for controlling the exposure amount controls the exposure amount to erase residual radiation energy to a level within the range between 0.01 and 0.0001 with the maximum of the originally stored radiation energy taken as 100.
References Cited (Backward Citations)
US4276473A
Cited
EP0022564A1
Cited
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