Apparatus for measurement of reflection density

• US 5,039,225 A
• Filed: 03/31/1989
• Issued: 08/13/1991
• Est. Priority Date: 04/01/1988
• Status: Expired due to Term

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Uekusa, Tadashi
• Primary Examiner(s): Rosenberger, Richard A.
• Assistant Examiner(s): PHAM, HOA Q
• Application Number:
  US07/331,121
• Time in Patent Office: 865 Days
• Field of Search: 356/445-448, 356/352, 356/73.1, 356/432, 356/433, 356/435, 356/444, 356/244, 356/237, 356/239, 436/530, 435/12
• US Class Current: 356/448
• CPC Class Codes: G01J 2001/1636 one detector directly monitoring the source, e.g. also impulse time controlling
• CPC Class Codes: G01N 2021/556 Measuring separately scattering and specular
• CPC Class Codes: G01N 21/474 Details of optical heads therefor, e.g. using optical fibres
• 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

An apparatus for measurement of optical reflection density of a surface of an article, such as a color developed analytical tape for clinical test. The apparatus comprises a support for supporting the article, a source of pulsed light and two light detectors. An optical guide directs the pulsed light to the surface of the article in a direction at an angle other than 90° to the surface of the article. A light-transmissive flat plate is arranged between the optical guide and the surface of the article and may be oriented at an angle from 0° to 90° with the surface of the article to be measured. One of the light-detectors detects a portion of the pulsed light reflected from the surface of the light-transmissive flat plate as reference light, and the second light-detector detects a vertically reflected portion of the pulsed light diffusely reflected on the surface of the article. Light detected from the second detector may be provided for analysis after comparison with respect to the reference light of the first detector.

Claims

1. An apparatus for measurement of optical reflection density of a clinical analytical tape comprising:

a flash lamp which emits a pulsed light;

a light-transmissive flat support for supporting the tape on one surface thereof, said support having a reflectance which permits reflection of 4-15% of said pulsed light;

light-guiding means for guiding said pulsed light to a surface of the tape in a direction at an angle other than 90°

to the surface of the tape;

a first light-detector for detecting reference light, which is a portion of said pulsed light reflected from the light-transmissive flat support; and

a second light-detector for detecting a portion of said pulsed light diffusely reflected from the tape, said portion being directed perpendicular to the surface of the tape.

2. The apparatus as claimed in claim 1, wherein said light-guiding means has at its end a lens for converging said pulsed light to be focused on the surface of the tape.

3. The apparatus as claimed in claim 1, wherein the flash lamp is a xenon flash lamp.

4. The apparatus as claimed in claim 1, wherein said light-guiding means is a quartz fiber, glass fiber or plastic fiber.