Patent US4820926A successfully refreshed from Google Patents.
US4820926A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiation conversion screen
Assignee: US Philips Corp
•
Filing: 1986-09-22
•
Granted: 1989-04-11
•
Expires: 2006-09-22
Abstract
Abstract A radiation conversion screen having sub-layers with mutually different radiation-conversion, radiation-optical and/or technological properties wherein successive sub-layers of luminescent material have a luminescent radiation absorption which decreases in the propagation direction of the radiation beam.
Inventors
- 👤 Theo J. A. Popma
- 👤 Jacob A. Den Boer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:17
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/36; H01J29/38; H01J29/385; G; G21; G21K; G21K4/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
95 words
A radiation conversion screen for detecting a propagating incident radiation beam, comprising a luminescent layer which is sensitive to said radiation and is composed of sub-layers which succeed one another in an intended direction of propagation of said radiation beam; each of said sub-layers having mutually different radiation-conversion, radiation-optical and/or technological properties wherein successive sub-layers of luminescent material have a luminescent radiation absorption which decreases in the intended propagation direction of the radiation beam; and means which orient said screen so that said radiation beam propagates in the intended direction with respect to the screen.
Claim 2
Dependent Claim
95 words
A radiation conversion screen for detecting a propagating incident radiation beam, comprising a luminescent layer which is sensitive to said radiation and is composed of sub-layers which succeed one another in an intended direction of propagation of said radiation beam; each of said sub-layers having mutually different radiation-conversion, radiation-optical and/or technological properties wherein successive sub-layers of luminescent material have a luminescent radiation absorption which decreases in the intended propagation direction of the radiation beam; and means which orient said screen so that said radiation beam propagates in the intended direction with respect to the screen.
Claim 3
Dependent Claim
22 words
A radiaton conversion screen as claimed in claim 1 wherein successive sub-layers contain the same material, but have a mutually different morphology.
Claim 4
Dependent Claim
29 words
A radiation conversion screen as claimed in claim 1 or 2 wherein the sub-layers have a structure noise which decreases in the intended propagation direction of the radiation beam.
Claim 5
Dependent Claim
39 words
A radiation conversion screen as claimed in claim 1 or 2 wherein a first sub-layer is a comparatively thin layer and a subsequent sub-layer in the intended propagation direction of the radiation beam is a comparatively thick, luminescent layer.
Claim 6
Dependent Claim
39 words
A radiation conversion screen as claimed in claim 1 or 2 wherein a first sub-layer is a comparatively thick luminescent layer and a subsequent sub-layer in the intended propagation direction of the radiation beam is a comparatively thin layer.
Claim 7
Dependent Claim
43 words
A radiation conversion screen as claimed in claim 1 or 2 wherein a first sub-layer is a comparatively thin layer of CaWO 4 and a subsequent sub-layer in the intended propagation direction of the radiation beam is a comparatively thick layer of BaFCl.
Claim 8
Dependent Claim
43 words
A radiation conversion screen as claimed in claim 1 or 2 wherein a first sub-layer is a comparatively thin layer of CaWO 4 and a subsequent sub-layer in the intended propagation direction of the radiation beam is a comparatively thick layer of CsI.
Claim 9
Dependent Claim
44 words
A radiation conversion screen as claimed in claim 1 or 2 wherein a first sub-layer is a comparatively thin layer of CaWO 4 and a subsequent sub-layer in the intended propagation direction of the radiation beam is a comparatively thick layer of Re oxibromide.
Claim 10
Dependent Claim
53 words
A radiation conversion screen as claimed in claim 1 or 2 wherein a first sub-layer is a comparatively thin layer which transmits luminescent light, a next subsequent sub-layer in the intended propogation direction of the radiation beam is a comparatively thick luminescent layer and a further subsequent sub-layer is a comparatively thin layer.
Claim 11
Dependent Claim
38 words
A radiation conversion screen as claimed in claims 1 or 2, further comprising a photographic film which is sensitive to the luminescent light which is disposed at a side of the screen from which the luminescent light emerges.
Claim 12
Dependent Claim
34 words
A radiation conversion screen as claimed in claims 1 or 2, further comprising a photocathode layer and wherein an adjacent first sub-layer is matched to technological, chemical or optical properties of said photocathode layer.
Claim 13
Dependent Claim
20 words
A radiation conversion screen as claimed in claim 11, comprising a further sub-layer of CsI having a reinforced columnar structure.
Claim 14
Dependent Claim
27 words
A radiation conversion screen as claimed in claim 12, comprising a further sub-layer which forms a comparatively thin, extremely dense top layer disposed over the luminescent layer.
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) | 1992-04-10 | 1992-10-10 | 1993-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-10 | 1996-10-10 | 1997-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-10 | 2000-10-10 | 2001-04-11 | $7700.00 | Window Closed / Lapsed |