Photoinitiated crosslinking polymerisation

The formation of densely crosslinked networks by chain crosslinking photopolymerization is discussed in relation to selected applications in the electronics industry. All of these applications make use of the high speed and of the latitude to meet other requirements by variation of the chemical structure of the monomers. The selection comprises:

1.

The coating of optical fibers;




2.

The replication of optical discs;




3.

The replication of aspherical lenses, used for laser read-out of these discs.

Network formation by chain crosslinking photopolymerization and some applications in electronics

A liquid crystal device includes a front electrode layer, a rear electrode layer, and a liquid crystal material located between the front electrode layer and the rear electrode layer. A first and second transistor each includes three terminals. The first transistor is a photo transistor. The first terminal of the first transistor electrically interconnected to a conductive electrode free from additional electrical elements therebetween. The second terminal of the first transistor is electrically interconnected to the conductive electrode free from additional electrical elements therebetween and the second terminal of the first transistor is maintained at the same potential as the conductive electrode. The first terminal of the first transistor and the second terminal of the first transistor electrically interconnected to one another free from additional electrical elements therebetween and the first terminal of the first transistor and the second terminal of the first transistor are maintained at the same potential. The second terminal of the first transistor is a gate of the first transistor. The third terminal of the first transistor electrically interconnected to the first terminal of the second transistor free from additional electrical elements therebetween and maintained at the same potential. The second transistor provides a readout function for the circuit. The second terminal of the second transistor electrically connected to one of the select electrodes. The second terminal of the second transistor is a gate of the second transistor. The third terminal of the second transistor is electrically interconnected to a readout system. The second transistor is substantially inhibited from receiving ambient light thereon. The first transistor is not substantially inhibited from receiving ambient light thereon. The first transistor and the second transistor being together with the rear electrode layer. The readout system determines a region of the device that experiences a change in the light level impinging on the device.

Light sensitive display

A thin, large, high-definition television screen employs optical waveguides. Light (32) flows through waveguides (28) arranged, in parallel, across a substrate (64). Light from a source (44) is coupled into the waveguides using a Graded Index (GRIN) microlens array (56). Taps (37) direct light out and make it visible at different locations along the length of the waveguides. Long interaction length (8) taps with deflectors (10) are introduced which enable many waveguides to be placed side-by-side and still maintain high screen resolutions. Polymers, both electro-optic and non-electro-optic, are used in one embodiment as a waveguide building material. However, acousto-optic, thermo-optic (86) and magneto-optic effects may also be used with other materials such as glass and silicon dioxide. This display can be economically produced by forming a flexible waveguide ribbon (62) which integrates multiple waveguides (1), intensity modulators (40) and taps (38) into a single unit. Waveguide manufacturing techniques based on thermo-poling, photolocking, extruding, preform fiber-drawing, and laser milling are also discussed.

Optical waveguide display system

A method and an apparatus for generating information input which are capable of realizing a direct command type information input scheme by which the gesture or the motion can be inputted easily. The apparatus has a timing signal generation unit for generating a timing signal; a lighting unit for emitting a light whose intensity vary in time, according to the timing signal generated by the timing signal generation unit; and a reflected light extraction unit having a sensor array for detecting a reflected light from a target object resulting from the light emitted by the lighting unit, in synchronization with the timing signal generated by the timing signal generation unit, so as to obtain a spatial intensity distribution of the reflected light in a form of a reflected light image indicative of an information input related to the target object, in separation from an external light that is illuminating the target object.

Method and apparatus for generating information input using reflected light image of target object

Polymer optical waveguides for multimode optical fiber systems have been formed by the selective photopolymerization method, and their waveguiding properties have been investigated. It is shown that the polymer optical waveguides match multimode optical fiber systems, with respect to guide dimensions and index differences, and have a transmission loss sufficiently low for circuit designs in the infrared region (0.19 dB/cm at 0.83 μm). In addition, effective applications of polymer optical circuits to compact optical dividers and lower loss couplers are demonstrated.

Polymer optical circuits for multimode optical fiber systems

A coordinate input apparatus. A pair of optical guide channel arrays each including a required number of parallel optical guide channels (11, 12) which contain optical scatterer (22) are superposed to form an input board (100) with the optical guide channels of the two arrays intersected at right angles. Light is detected which is scattered by the optical scatterer (22) in the optical guide channels (11, 12) corresponding to irradiation of one point on the input board by a light pen (10) and reaches end surfaces (11a, 12a) of the optical guide channels. The detected signals are processed to form a binary signal train representative of the coordinate of the light pen (10).

Coordinate input apparatus

A polymer optical circuit with optical lead-fibers which comprise a plurality of optical fibers, each one end portion thereof being embedded in a transparent polymer film formed on a substrate, and polymer optical waveguides formed in the film between the embedded ends of the optical fibers so that the terminal ends of the optical waveguides are connected with the embedded ends of the optical fibers; the substrate, polymer film, polymer optical waveguide and optical fibers being formed as an integrated unit. A process for fabricating this polymer optical circuit is also disclosed.

Polymer optical circuit with optical lead-fibers and method of fabricating the same

Fiber optic sheets (8 lines/mm), applicable as image convertors in a facsimile input system, have been formed by a selective monomer photopolymerization in polymer films. In this method, the monomer is doped in a plane film with a higher refractive index and then photopolymerized selectively through a mask pattern by uv light irradiation, so that all light paths are formed simultaneously, instead of arranging individual optical fibers. The attenuation was 0.15–0.20 dB/cm at λ = 633 nm, and the output light intensity distribution formed by a test chart through light paths showed a resolution of up to ∼5 lines/mm.

Fiber optic sheet formation by selective photopolymerization

A polymer waveguide star coupler formed by the selective photopolymerization method is described. This polymer waveguide star coupler has low insertion loss independent of the core and cladding dimensions of the optical fiber. The six-port star coupler obtained, with input and output fiber arrays, had an insertion loss of 2.6 dB and a loss variation across the six ports of 1.2 dB at 0.84 μm.

Norio Takato

Papers

Polymer optical circuits for multimode optical fiber systems

Coordinate input apparatus

Polymer optical circuit with optical lead-fibers and method of fabricating the same

Fiber optic sheet formation by selective photopolymerization

Polymer waveguide star coupler