Abstract: An article is manufactured from a substrate of a material that exhibits the pyroelectric effect by depositing a film containing a selected material in a first state over a front surface of the substrate. At least one electrode is formed on the film, portions of the film being exposed around the electrode. The exposed portions of the film are subjected to a treatment such that they are converted from the first state to a second state, in which the material has a resistivity that lies within a desired range of values.

Abstract: An electrooptic directional coupler having first and second electrodes for influencing coupling between a segment of a first optical waveguide and a segment of a second optical waveguide, is operated by varying the potential of the first electrode relative to the second electrode during a first interval in accordance with a first function such that the first electrode remains at a first polarity relative to the second electrode, and varying the potential of the first electrode relative to the second electrode during a second interval in accordance with a second function such that the first electrode remains at a second polarity, opposite the first polarity, relative to the second electrode. The integral with respect to time over the first and second intervals of the potential of the first electrode relative to the second electrode is essentially zero.

Abstract: An electrooptical device comprises a substrate of electrooptic material having first, second and third optical waveguide formed therein. The first and second waveguides have first and second waveguide segments respectively, and the third waveguide has third and fourth waveguide segments extending adjacent the first and second waveguide segments respectively, so that first and second directional couplers are formed. The interaction length of the first directional coupler is slightly greater than an optimum interaction length for a predetermined wavelength and the interaction length of the second directional coupler is slightly less than an optimum interaction length for the predetermined wavelength. A first electrode structure influences the first directional coupler and a second electrode structure influences the second directional coupler.

Abstract: A non-linear amplifier system for a repetitive input signal includes a first amplifier stage for amplifying low level input signals, including noise, in a linear manner and higher level input signals in a non-linear manner. A sampling circuit smooths the output from the first amplifier stage and thereby reduces the amplitude of low level random noise signals. A second amplifier stage receives the output from the sampling circuit and amplifies in a non-linear manner signals corresponding to low level input signals of the first amplifier stage and amplifies in linear manner signals corresponding to higher level input signals of the first amplifier stage. Consequently, low level input signals can be amplified in non-linear manner without introducing substantial errors due to non-linear amplification of low level random noise signals.