CA2233596A1
Expired / Lapsed
CA
⏱️ 0.0 years remaining
Ultraviolet sensing apparatus
Assignee: Advanced Systems Ltd
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Filing: 1996-10-30
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Granted: —
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Expires: 2016-10-30
Abstract
Abstract UV sensing apparatus comprises a substantially light-proof housing (1), an aperture (1a) formed in the housing, a filter (2) positioned within the housing at the internal mouth of the aperture, a fluorescent member (3) positioned within the housing on that side of the filter remote from that adjacent to the aperture, and a light sensor (4) positioned within the housing to receive light emitted by the fluorescent member. The filter (2) is such that it substantially removes visible light, the fluorescent member (3) is such as to fluoresce when subjected to UV radiation, and the light sensor (4) is positioned so that substantially none of any electromagnetic radiation entering the housing (1) via the aperture (1a) impinges upon the light sensor.
Inventors
- 👤 Anthony George Standfast Piper
- 👤 David Michael Hodgkinson
- 👤 Adrian Kenworth Taylor
- 👤 Martin Thomas Pickering
- 👤 Roderick Nigel Jones
- 👤 Gresham Randal Thomas Clacy
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-10-27 15:08
CPC Classifications
G; G01; G01J; G01J1/00; G01J1/58; G01J1/42; G01J1/429
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
176 words
UV sensing apparatus comprising a housing which is substantially opaque to electromagnetic radiation, an aperture formed in the housing, a filter positioned within the housing at the internal mouth of the aperture, a fluorescent member positioned within the housing on that side of the filter remote from that adjacent to the aperture, and a light sensor positioned within the housing to receive light emitted by the fluorescent member, wherein the filter is such that it substantially removes visible light, the fluorescent member is such as to fluoresce when subjected to UV radiation, and the light sensor is positioned so that, without the provision of a second filter, substantially none of any electromagnetic radiation entering the housing via the aperture impinges upon the light sensor, and wherein the internal geometry of the apparatus and the size of the aperture are such as to constrain the angles of electromagnetic radiation entering the apparatus so that IR radiation is not reflected internally within the fluorescent member at angles which allow the IR radiation to egress towards the light sensor.
Claim 2
Dependent Claim
176 words
UV sensing apparatus comprising a housing which is substantially opaque to electromagnetic radiation, an aperture formed in the housing, a filter positioned within the housing at the internal mouth of the aperture, a fluorescent member positioned within the housing on that side of the filter remote from that adjacent to the aperture, and a light sensor positioned within the housing to receive light emitted by the fluorescent member, wherein the filter is such that it substantially removes visible light, the fluorescent member is such as to fluoresce when subjected to UV radiation, and the light sensor is positioned so that, without the provision of a second filter, substantially none of any electromagnetic radiation entering the housing via the aperture impinges upon the light sensor, and wherein the internal geometry of the apparatus and the size of the aperture are such as to constrain the angles of electromagnetic radiation entering the apparatus so that IR radiation is not reflected internally within the fluorescent member at angles which allow the IR radiation to egress towards the light sensor.
Claim 3
Dependent Claim
41 words
UV sensing apparatus as claimed in claim 1, wherein the refractive indices of IR within the apparatus are such that IR is not reflected internally within the fluorescent member at angles which allow the IR to egress towards the light sensor.
Claim 4
Dependent Claim
44 words
UV sensing apparatus as claimed in claim 1 or claim 2, wherein the light sensor is shielded by an internal housing wall in such a manner that substantially none of any electromagnetic radiation entering the housing via the aperture impinges upon the light sensor.
Claim 5
Dependent Claim
52 words
UV sensing apparatus as claimed in any one of claims 1 to 3, wherein the aperture is sized so that electromagnetic radiation entering the sensing apparatus is insufficient to cause saturation of the fluorescent member, and so that the light sensor is not saturated by the light emitted by the fluorescent member.
Claim 6
Dependent Claim
33 words
UV sensing apparatus as claimed in any one of claims 1 to 4, wherein the aperture is circular and has a diameter lying within the range of from 0.25 mm to 3 mm.
Claim 7
Dependent Claim
25 words
UV sensing apparatus as claimed in claim 5, wherein the aperture has a diameter lying within the range of from 0.75 mm to 2 mm.
Claim 8
Dependent Claim
23 words
UV sensing apparatus as claimed in any one of claims 1 to 6, wherein the filter is made of a dark blue glass.
Claim 9
Dependent Claim
36 words
UV sensing apparatus as claimed in any one of claims 1 to 7, wherein the fluorescent member is an acrylic slab coated on one side with an organic dye which fluoresces when subjected to UV radiation.
Claim 10
Dependent Claim
23 words
UV sensing apparatus as claimed in claim 8, wherein the coated side of the acrylic slab is that side adjacent to the filter.
Claim 11
Dependent Claim
35 words
UV sensing apparatus as claimed in any one of claims 1 to 7, wherein the fluorescent member is an acrylic slab which is doped with an organic dye which fluoresces when subjected to UV radiation.
Claim 12
Dependent Claim
20 words
UV sensing apparatus as claimed in any one of claims 8 to 10, wherein the organic dye is a phosphor.
Claim 13
Dependent Claim
31 words
UV sensing apparatus as claimed in any one of claims 8 to 11, wherein the dye is such as to emit light of a predetermined frequency when subjected to UV radiation.
Claim 14
Dependent Claim
18 words
UV sensing apparatus as claimed in claim 12, wherein the dye is such as to emit green light.
Claim 15
Dependent Claim
37 words
UV sensing apparatus as claimed in any one of claims 1 to 13, wherein the fluorescent member is such that the intensity of fluorescent light emitted is substantially linearly proportional to the intensity of UV radiation received.
Claim 16
Dependent Claim
21 words
UV sensing apparatus as claimed in any one of claims 1 to 14, wherein the light sensor is a light-dependent resistor.
Claim 17
Dependent Claim
24 words
UV sensing apparatus as claimed in claim 15, wherein the resistance of the light-dependent resistor varies linearly with the intensity of the received light.
Claim 18
Dependent Claim
51 words
UV sensing apparatus as claimed in claim 8, or in any one of claims 9 to 16 when appendant to claim 8, wherein the light sensor is positioned at an edge of the acrylic slab so that fluorescent light passes to the light sensor only by internal reflection within the slab.
References Cited (Backward Citations)
No citation records indexed.
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