A source of optical wave energy for an optical communication system. One end of an optical waveguide fiber bundle is disposed in light-receiving relationship with respect to light from a Lambertian-type light source such as a light emitting diode. A spherical bead of transparent material disposed between the diode and the fiber bundle endface provides a rugged and inexpensive optical device that tends to collimate the light emitted from the diode.

Light source for optical waveguide bundle

Radial gradient index of refraction (GRIN) optical relays are described for overcorrecting axial chromatic aberration. In particular, a relay including a negative dispersion radial GRIN rod alone or in combination with simple homogeneous or GRIN lenses is described for adjusting axial chromatic and monochromatic aberrations, including spherical, coma, astigmatism, and distortion. The invention also describes remote viewing scopes, such as endoscopes and borescopes, which utilize GRIN relays for achromatic, and reduced or corrected monochromatic aberration imaging The use of segmented GRIN relays provides a degree of flexibility in remote viewing scopes.

Negative abbe number radial gradient index relay and use of same

A miniature optical lens for coupling is fabricated from selected high rective index semiconductor material of uniform thickness. Refractive index gradients are generated in the semiconductor material through changes in composition developed under controlled conditions producing a desired focal length for determinable wavelengths of light energy emitted from a light source to which the miniature optical lens is coupled. The miniature optical lens thus fabricated is especially efficient for coupling light energy from light emitting diodes and junction lasers as well as in semiconductor micro-optics within the visible and the infrared wavelengths as well because the index of refraction of the lens material may be closely matched to the index of refraction of the light source, minimizing light energy transfer losses.

Gradient index miniature coupling lens

An objective of variable focal length includes a plurality of lens units of which the first, counting from front, is of negative power and the second is of positive power. At least the first and second lens units are moved with variation of the air separation therebetween to vary the focal length of the entire system. The objective is characterized in that at least one of the lens units is included with at least one refractive index distribution type lens arranged on the common optical axis of the other lenses.

Objective of variable focal length

Diffractive lenses having gradial zones (62, 70, 78, 90, 98, 106, 114) are formed by separately, sequentially spin casting and polymerizing successive radial zones of the lens to produce optical phase differences of 2π between adjacent gradial zones. Diffractive lenses may be molded in plano-plano (60), plano-concave (68) and planoconvex (76) geometries and also may be combined with conventional plano-plano (84), convex-convex (92), plano-concave (100) and plano-convex (108) refractive lenses.

Gradial zone lens and method of fabrication

Disclosed herein is a photoelectric converter including a convergent lens with a transparent member having a refractive index distribution, in a cross section perpendicular to a travelling axis of light, so as to substantially satisfy the equation: NR NO(1-AR2) WHEN A REFRACTIVE INDEX AT THE CENTER OF THE CROSS SECTION IS NO, A REFRACTIVE INDEX AT A DISTANCE R FROM THE CENTER IS NR AND A POSITIVE CONSTANT IS A.

Hidetoshi Togo

Papers

Photoelectric converter including convergent lens with refractive index distribution