Optical encoder with encapsulated electrooptics

An optical encoder for sensing modulated light reflected form a movable member, the sensor comprising:

• a light emitting device having a light output for illuminating the movable member;
• at least one photodetector for detecting the modulated light reflected from the movable member;
• a transparent medium encapsulating the light emitting device and the photodetector;
• and
• a lens surface on the medium in an optical path defined between the light emitting device, the movable member, and the photodetector, wherein the lens surface comprises an emitter lens located in the optical path between the light emitting device and the movable member for concentrating the light output from the light emitting device before it illuminates the movable member.

An optical encoder for sensing modulated light reflected from a movable member, the sensor comprising:

• a light emitting device having a light output for illuminating the movable member;
• at least one photodetector for detecting the modulated light reflected from the movable member;
• a transparent medium encapsulating the light emitting device and the photodetector;
• and
• a lens surface on the medium in an optical path defined between the light emitting device, the movable member, and the photodetector, wherein the lens surface comprises a detector lens located in the optical path between the movable member and the photodetector for concentrating the modulated light before the modulated light is detected by the photodetector.

An optical encoder for sensing modulated light reflected from a movable member, the sensor comprising:

• a light emitting device having a light output for illuminating the movable member;
• at least one photodetector for detecting the modulated light reflected from the movable member;
• a transparent medium encapsulating the light emitting device and the photodetector;
• and
• a lens surface on the medium in an optical path defined between the light emitting device, the movable member, and the photodetector, wherein the lens surface comprises first and second convex spherical surfaces;
• the first convex spherical surface forming an emitter lens between the light emitting device and the movable member, the light emitting device being located at a greater distance from the first convex spherical surface than the vertex of the emitter lens;
• and
• the second convex spherical surface forming a detector lens between the movable member and the photodetector, the photodetector being located at a greater distance from the convex surface of the detector lens than the vertex of the detector lens.

An optical encoder comprising:

• a light emitting device for emitting light along an optical path;
• a movable member positioned in the optical path having alternating reflective and nonreflective areas for modulating light from the light emitting device in response to movement of the member,
• at least one photodetector positioned in the optical path for detecting the modulated light;
• an emitter lens covering the light emitting device for preventing light not modulated in response to the movement of the movable member from reaching the photodetector;
• and
• a detector lens for concentrating the modulated light from the movable member toward the photodetector, wherein the width of each cycle of photodetector area is twice the width of each cycle of reflective and nonreflective areas on the movable member divided by magnification of the detector lens.

An optical encoder comprising:

• a movable code member having alternating reflective and nonreflective areas;
• a platform;
• a light emitting device located on the platform for illuminating reflective areas on the code member;
• a photodetector located on the platform for receiving light reflected from such reflective areas, the light emitting device nd photodetector being located on the same side of the code member;
• a transparent encapsulant embedding the light emitting device and the photodetector;
• and
• a convex surface on the encapsulant in the optical path between the light emitting device, the code member and the photodetector.