Optical sensor having atomically localized luminescence centers

• US 4,569,570 A
• Filed: 05/26/1983
• Issued: 02/11/1986
• Est. Priority Date: 05/27/1982
• Status: Expired due to Fees

• Current Assignee: ASEA Aktiebolafg Vasteras Sweden
• Original Assignee: Asea Aktiebolag (ABB Limited)
• Inventors: Brogardh, Torgny, Hok, Bertil, Ovren, Christer
• Primary Examiner(s): Lee, John
• Assistant Examiner(s): Rushin, III, Lester
• Application Number:
  US06/498,477
• Time in Patent Office: 992 Days
• Field of Search: 252/301.16, 250/485.1, 250/486.1, 350/96.29, 350/96.30, 350/96.1, 350/96.34, 372/40, 372/41
• US Class Current: 385/12
• CPC Class Codes: G01B 11/18 using photoelastic elements
• CPC Class Codes: G01D 5/268 using optical fibres G01D5/28 - G01D5/38 take precedence
• CPC Class Codes: G01K 11/3213 using changes in luminescence, e.g. at the distal end of the fibres

Abstract

An optical sensor for detecting changes in physical quantities such as temperature, position, force, level, pressure, flow, acceleration, magnetic or electrical field strength or mechanical deformation, includes a luminescent material built up of atomically localized luminescence centers, included as a solid solution in an amorphous or mono-crystalline bonding material.

Claims

1. An optical sensor for detecting a change in a physical quantity, said optical sensor comprising two spaced apart bodies, each of said two bodies comprising a solid, substantially optically transparent bonding material which is in the shape of an optical wave conductor and which contains at least 1% by weight of a luminescent material in the form of localized luminescent centers in solid solution, the luminescent materials in said two bodies being different such that the luminescent light emitted from each when excited by light from a common light source will have different optical properties, said two bodies being physically separated but close enough to one another that excitation light from a first of said two bodies can be received by the second of said two bodies and luminescent light from the second of said two bodies can be received by the first of said two bodies.

2. The optical sensor according to claim 1, wherein the localized luminescent centers contained in each of said two bodies are in the form of ions.

3. The optical sensor according to claim 2, wherein said ions consist of rare earth metal ions.

4. The optical sensor according to claim 1, wherein said bonding material is electrically insulating and wherein it includes at least one oxide of a metal selected from the group consisting of silicon, boron, germanium and phosphorus.

5. The optical sensor according to claim 1, wherein the bonding materials and luminescent materials therein used in making each of the two bodies are such that the luminescent light emitted thereby is independent of the temperature to which they are subjected over a predetermined temperature range.

6. The optical sensor according to claim 1, wherein the bonding materials and luminescent materials therein used in making each of the two bodies are such that the luminescent light emitted thereby varies with a change in the temperature to which they are subjected over a predetermined temperature range.

7. The optical sensor according to claim 1, including a fiber for transmitting excitation light to the first of said two bodies and to receive luminescent light emitted from the first of said two bodies.