Light reflective opti-mechanical displacement microindicator
First Claim
1. A displacement indicator comprising a light transmitting member having two opposite surfaces and a light absorbing member disposed at one surface of said light transmitting member, said one surface of said light transmitting member having a faceted light reflective configuration, said light transmitting member and said light absorbing member being moveable relative to each other between two end positions, in one end position said light reflective surface of said light transmitting member is in intimate contact with the adjacent surface of said light absorbing member whereby incident light passing through said light transmitting member is absorbed by said light absorbing member and in the other end position said members are spaced from each other producing an air gap between said reflective surface and said adjacent surface of said light absorbing member whereby incident light is internally reflected at said reflective surface and passes out of said light transmitting member.
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Accused Products
Abstract
An indicator for optically indicating small displacements or changes in displacement of one member relative to another member, comprising a light transmitting member having a faceted light reflective under surface, and an opaque, light absorbing member disposed beneath the light transmitting member, whereby when the two members are separated by a thin film of air, incident light transmitted through the transmitting member is totally internally reflected at the under surface displaying a bright appearance to an observer. When the two members are forced into intimate contact by a displacement to be indicated, the incident light is absorbed by the second member and a dark appearance is presented to an observer. The light absorbing member'"'"'s upper surface may be a negative replica of the under surface of the transmitting member in which case an abrupt change in transmitted light is observable upon a displacement, or the absorbing member may have a flat upper surface formed of an elastomeric material so that there is a gradually increasing area of contact between the two members and a more gradual change in appearance from bright to dark.
52 Citations
13 Claims
- 1. A displacement indicator comprising a light transmitting member having two opposite surfaces and a light absorbing member disposed at one surface of said light transmitting member, said one surface of said light transmitting member having a faceted light reflective configuration, said light transmitting member and said light absorbing member being moveable relative to each other between two end positions, in one end position said light reflective surface of said light transmitting member is in intimate contact with the adjacent surface of said light absorbing member whereby incident light passing through said light transmitting member is absorbed by said light absorbing member and in the other end position said members are spaced from each other producing an air gap between said reflective surface and said adjacent surface of said light absorbing member whereby incident light is internally reflected at said reflective surface and passes out of said light transmitting member.
Specification