Reflection plate for a biochemical measuring instrument

• US 5,120,507 A
• Filed: 11/17/1988
• Issued: 06/09/1992
• Est. Priority Date: 11/24/1987
• Status: Expired due to Term

• Current Assignee: Omron Tateisi Electronics Co. (Omron Corporation), Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Boehringer Mannheim Corporation, Omron Tateisi Electronics Co. (Omron Corporation)
• Inventors: Sierra, George H., Sano, Yoshihiko, Zivitz, Maury, Makita, Shigeru
• Primary Examiner(s): Johnston, Jill A.
• Application Number:
  US07/272,365
• Time in Patent Office: 1,300 Days
• Field of Search: 422/68.1, 422/82.05, 350/110, 356/238, 356/408
• US Class Current: 422/82.05
• CPC Class Codes: G01N 2021/478 Application in testing analytical test strips
• CPC Class Codes: G01N 21/4785 Standardising light scatter apparatus; Standards therefor
• CPC Class Codes: G01N 21/8483 Investigating reagent band test-element handling not specific to a test method G01N33/4875; analytical elements specific to chemical analysis of biological material G01N33/52; autometer with reagent band G01N35/04

Abstract

A reflection plate for a biochemical measuring instrument which is adapted to evaluate a biochemical value by obtaining a reflective property of a reflection surface of the reference reflection plate, obtaining a reflective property of test paper impregnated with biochemical sample and mounted on a test stick, and comparing the two reflective properties, wherein: the reflection surface of the reference reflection plate is depressed from the periphery thereof. Thereby, even though the test stick is required to be placed adjacent to the reflection surface to achieve a uniformity the optical arrangement in obtaining the two reflective properties, the contamination of the reflection surface from the sample can be prevented. Preferably, the reference reflection plate itself may be provided with a depression to defined the reflection surface at the bottom of this depression.

Claims

1. A biochemical measuring instrument comprising:

a reference reflection plate;

reflection sensor means for obtaining a reflective property of a reflection surface of said reference reflection plate and for obtaining a reflective property of a test paper impregnated with a biochemical sample and mounted on a test stick inserted in said instrument between the reference reflection plate and the reflection sensor means; and

evaluating means for evaluating a biochemical value of the biochemical sample by comparing the two reflective properties,

wherein said reflection surface of said reference reflection plate is depressed from the periphery of said reference reflection plate, is substantially flat and is disposed parallel to a direction of insertion of the test stick.

3. A biochemical measuring instrument as defined in claim 1, further comprising a test stick holder having a window formed therein adapted to hold a test stick inserted therethrough, said window being disposed such that a test paper mounted on the test stick inserted therethrough is held between the reference reflection plate and the reflection sensor means.

2. A biochemical measuring instrument as defined at a portion of the bottom surface of said reference reflection plate depressed from the periphery.