Reflectometer

• US 4,484,819 A
• Filed: 06/16/1982
• Issued: 11/27/1984
• Est. Priority Date: 06/16/1982
• Status: Expired due to Fees

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Ulrich, Richard D.
• Primary Examiner(s): McGraw, Vincent P.
• Application Number:
  US06/388,863
• Time in Patent Office: 895 Days
• Field of Search: 356/445, 356/446, 356/447, 356/448, 235/472
• US Class Current: 356/446
• CPC Class Codes: G01N 21/474 Details of optical heads therefor, e.g. using optical fibres

Abstract

A portable reflectometer is made using a diffuse light and light sensor cination to measure reflectivity of solar wavelengths. A cadmium sulfide photocell is used as the light sensor connected to a voltage divider network which provides a linear response to an internal light source. The light shield is placed around the light source and the light sensor to limit detected light to only that reflected on the surface due to the diffuse light source. The invention is mounted in a hand-held gun configuration to provide easy use.

Claims

1. A surface reflectometer comprising:

a tube with an open end;

a light source mounted within said tube;

a reflector mounted within said tube and around said light souurce, such that light from said light source is reflected towards said tube'"'"'s open end;

a diffuser placed in said tube such that all of said light traveling towards said tube'"'"'s open end must pass through said diffuser prior to reaching said tube'"'"'s open end;

a light sensor placed in between said diffuser and said tube'"'"'s open end, said light sensor only receiving light into said tube from said tube'"'"'s open end;

an electrical circuit connected to said light sensor to measure the amount of light colected by said light sensor;

display means connected to said electrical circuit to display the amount of light received by said light sensor; and

a light shield around said light tube'"'"'s open end.

2. A surface reflectometer as described in claim 1 where said light sensor comprises a cadmium sulfide photocell sensor.

3. A surface reflectometer as described in claim 2 where said electrical circuit further comprises a voltage divider network connected to said cadmium sulfide cell.

4. A surface reflectometer as described in claim 3 where said display means comprises a liquid crystal display.