Wearable transmitter with optical tamper detection

• US 5,650,766 A
• Filed: 04/24/1995
• Issued: 07/22/1997
• Est. Priority Date: 04/24/1995
• Status: Expired due to Term

• Current Assignee: Detection Systems, Inc. (IKUSI - Angel Iglesias SA)
• Original Assignee: Detection Systems, Inc. (IKUSI - Angel Iglesias SA)
• Inventors: Burgmann, Thomas Anthony
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US08/427,522
• Time in Patent Office: 820 Days
• Field of Search: 340/539, 340/573, 340/555, 340/693, 340/568, 361/173-177, 200/DIG. 2, 200/DIG. 47, 200/DIG. 36
• US Class Current: 340/539.11
• CPC Class Codes: G08B 21/22 responsive to presence or absence of persons
• CPC Class Codes: Y10S 200/02 Body attached switches
• CPC Class Codes: Y10S 200/36 Light operated switches
• CPC Class Codes: Y10S 200/47 Light guides for switch indicators, e.g. prisms, reflectors or cables

Abstract

A wearable transmitter assembly includes a housing containing a radio frequency transmitter and tamper detecting circuit that are attached to an appendage of an individual with a buckle and strap. A light emitter and a light sensor are disposed in the housing and extend to the outside of the housing through one or more apertures. The strap includes an embedded optical fiber. Attachment of the housing to the buckle positions the emitter and sensor adjacent the ends of the optical fiber in the strap to complete an optical path or circuit from the emitter around the appendage to the sensor. The housing is sealed closed, including sealant between the emitter, the sensor and the aperture, providing a water tight enclosure for said transmitter from the time of its manufacture. Attachment of the housing to the buckle completes a seal blocking contaminates, such as water, water vapor, and soap from the ends of the optical fiber, the emitter and the sensor.

Claims

1. A transmitter assembly including a housing containing a radio frequency transmitter and circuit board, a strap defining first and second ends, and a buckle for attaching the strap and housing to an appendage of an individual;

characterized in that;

said housing defines at least one aperture, a light emitter and a light sensor are disposed on said circuit board projecting through said at least one aperture, said strap includes an optical fiber running through said strap from said first end to said second end, said buckle aligns said first and second ends in first and second predetermined positions relative to said buckle, and attachment of said housing to said buckle positions said emitter and sensor in said first and second predetermined positions, in optical communication with said first and second ends respectively, completing an optical path from said emitter through said optical fiber to said sensor.

2. The invention of claim 1, wherein said housing is sealed closed, including sealant between said emitter, said sensor and said at least one aperture, to provide a water tight enclosure for said transmitter.

3. The invention of claim 2, wherein said attachment of said housing to said buckle completes a seal blocking contaminates from said optical communication between said first and second ends of said optical fiber and said emitter and sensor, respectively.

4. The invention of claim 3, wherein said seal is a resilient member defining a compartment for receiving said emitter and said sensor, first and second opposed holes through said seal to said compartment for receiving first and second ends of said optical fiber, respectively, and a lip compressed by attachment of said transmitter to said buckle, thereby sealing said compartment closed.

5. The invention of claim 1, wherein said emitter is disposed closely adjacent said sensor on said circuit board, and said emitter and sensor are disposed in back-to-back relationship, with directions of view one hundred and eighty degrees apart parallel to said circuit board.

6. A transmitter assembly including a tamper detection circuit and attachable to a buckle for completing said circuit optically around an appendage of an individual;

said assembly comprising;

a housing defining a chamber and a side of said housing having at least one aperture from said chamber through said side;

means supporting said tamper detection circuit in said chamber, said tamper detection circuit including a light emitter and a light sensor projecting through said at least one aperture in said housing side;

means for sealing said chamber closed against water, including said at least one aperture; and

,

means on said side of said housing for pivoting said housing into latched position on the buckle, said pivoting completing said circuit optically from said emitter around the appendage to said sensor.

7. A transmitter assembly wearable on an appendage of an individual and comprising:

a housing defining a chamber and at least one aperture from said chamber through said housing;

a tamper detection circuit in said chamber, said tamper detection circuit including a light emitter and a light sensor extending through said at least one aperture in said housing;

means for sealing said chamber closed against water, including said at least one aperture;

a strap including first and second ends and an optical fiber running through said strap from said first end to said second end; and

,

a buckle including a) locating means independent of said housing for locating said first and second ends in first and second predetermined positions on said buckle, and b) fastening means for securely fastening said transmitter to said band with said optical fiber completing an optical circuit between said emitter and said sensor.

8. The invention of claim 7, wherein said emitter is supported closely adjacent said sensor, and said emitter and sensor are disposed in back-to-back in oppositely facing relationship.