Abstract: The concept of using only a component of an applied electric field to control the electrooptic response in each element of a multi-crystal electrooptic modulator comprising a matched grouping of birefringent electrooptic elements is disclosed. The foregoing concept permits the orientation of the polarization eigenvectors of the grouped elements to compensate for the effects of the static birefringence of the material comprising the elements while retaining the use of parallel applied electric fields and eliminating the need for an interposed optical rotator or waveplate.

Abstract: An apparatus for efficiently coupling laser light to multi-mode fiber uses a solid state laser focussed by a spherical microlens onto a partially reflecting mirror. The mirror is formed by polishing the ends of two fibers at 45 degrees and assembling them such that the ends abut and are substantially parallel. High efficiency is obtained by using the spherical lens to direct most of the laser light into the acceptance cone of the fiber and by orienting the laser such that the electric vector of the light is perpendicular to the fiber axis.

Abstract: An apparatus for maintaining one end of an optical fiber and a focusing lens is provided including means for adjustably focusing a beam of light onto the end of the fiber. The adjustable focusing means includes a means for pivoting the focusing lens and fiber to provide a very fine adjustment to direct the light beam into the core at the end of the optical fiber. The subject device includes a framework for maintaining the lens and one end of the optical fiber in a precisely controlled relationship. The adjustable focusing means may further include at least one screw in threaded engagement with the base portion of the device. One end of the screw contacts a peripheral portion of the maintaining means so that rotation of the screw causes the maintaining means to pivot about the end of the optical fiber.

Abstract: A method and an apparatus is disclosed for making an evanescent wave coupler. Two optical waveguides have a portion of the cladding material removed until the core is exposed. The two optical waveguides are placed in juxtaposition with an interleaf film between them. The interleaf film insures an accurate and constant spatial relation between the two optical waveguides to have reliable evanescent coupling therebetween.

Abstract: An apparatus is disclosed for optically sensing pressure using evanescent wave coupling between two fiber optics. A support base with a channel holds the two waveguides, one on top of the other, with the portion of the waveguide having the cladding material removed in the channel. An upper member having a diaphragm is attached to the support base. The diaphragm has a pedestal attached that is in slight contact with one of the waveguides. When pressure is exerted upon the diaphragm, the waveguides are forced closer together thus affecting the amount of evanescent coupling therebetween.

Abstract: An ink composition, suitable for use in jet printing, comprises a dye in a solvent consisting of water and lower alkylene glycol which is highly soluble in both water and the lower alkylene glycol, which is chemically stable for long periods in the solvent, has high tinctorial power and is resistant to fading by light. The ink composition is characterized by its ability to reduce the evolution of gases from solution at reduced pressure. The ink composition is further characterized by an adjusted pH of about 3 to about 6. In addition, the ink composition may contain preservatives to prevent fungus and bacteria growth.