Abstract: The present invention is directed to cinnolinyl and quinolinyl pyrazol-4-yl-pyridine compounds which are allosteric modulators of the M4 muscarinic acetylcholine receptor. The present invention is also directed to uses of the compounds described herein in the potential treatment or prevention of neurological and psychiatric disorders and diseases in which M4 muscarinic acetylcholine receptors are involved. The present invention is also directed to compositions comprising these compounds. The present invention is also directed to uses of these compositions in the potential prevention or treatment of such diseases in which M4 muscarinic acetylcholine receptors are involved.

Abstract: A laser radar system employing a linear FM chirp laser followed by post detection pulse compression by a surface acoustic wave (SAW) device. The system includes an FM chirp modulator that provides the needed tuning range and linearity for pulse compression. This modulation is accomplished by using a high-pressure CO.sub.2 laser with an intracavity electro-optic modulator of CdTe. The frequency of the transmitter laser is accurately controlled through the application of high linearity, high frequency, sawtooth voltages to the two plates of the CdTe crystal, with the voltage waveform applied to one plate being out of phase with that applied to the other crystal plate. With the performance the system offers, absolute radar ranges can be measured to 0.22 m and velocities to 0.37 m/sec.

Abstract: A laser radar system employing a linear FM chirp laser followed by post detection pulse compression by a surface acoustic wave (SAW) device. The heart of the invention is the FM chirp modulator that provides the needed tuning range and linearity for pulse compression. This modulation is accomplished by using a high pressure CO.sub.2 laser with an intracavity electric-optic modulator of CdTe. The frequency of the laser is controlled through the voltage applied to the crystal. With the performance the system offers, absolute radar ranges can be measured to 0.22 m and velocities to 0.37m/sec.

Abstract: A chirp laser system includes an intracavity electro-optical crystal modulated at a relatively high frequency, for example 250 kilohertz, to sweep the frequency of the transmitter laser above and below its nominal center frequency. One of the mirrors of the laser transmitter is adjustable to vary the length of the cavity and to shift the frequency of the transmitter laser. When the frequency of the transmitter laser is shifted, the output amplitude of the laser changes. With the center frequency of the laser at a maximum gain point, the amplitude of the output signals during positive and negative frequency excursions of the transmitter laser will be substantially symmetrical. However, if thermal or other effects cause the frequency of the laser to shift away from the maximum gain point, the output during positive and negative excursions will be asymmetrical.

Abstract: An imaging apparatus which permits the use of a transverse electrode electro-optic tunable filter (TEOTF), despite its obscured aperture, to produce a high quality image. The imaging apparatus includes a suitable conventional anamorphic input optical system in combination with a stacked plurality of TEOTFs in which the platelet of each TEOTF is made of an electro-optic material of a known index of refraction (such as CdS of an index of .about.2.4), and is clad between its surface and its electrodes with a material having a lower index of refraction than the platelet material (such as SiO.sub.2 of an index of .about.1.5).

Abstract: Apparatus for encoding a laser beam with information indicative of position in the beam. A linearly polarized laser beam passes through a birefringent wedge which encodes a continuously varying polarization across one dimension thereof. The polarization-encoded laser beam is applied to an electro-optic modulator which induces a second harmonic component of an applied modulation signal to appear in the beam due to optical biasing by the polarization encoding. On beam center, only the fundamental appears, while going away from beam center the second harmonic appears, having a varying magnitude and phase. A polarizer transmits a linearly polarized component of the encoded beam. To encode a second dimension of the beam orthogonal to the first, a second wedge and modulator are provided. To provide discrimination between the two, the second modulator operates at a different fundamental modulation frequency.

Abstract: Apparatus for coding a laser beam to provide guidance signals, or the like. In the transmitter, the laser beam traverses two modulators to provide two-dimensional encoding. In the receiver, the detected signals are amplified, frequency-discriminated, and mixed to form guidance signals. The modulator is a modified Stark cell wherein four split longitudinal planar electrodes allow for beam encloding as a function of two frequencies by the process of molecular absorption. Bias and modulating signals applied to the electrodes interact with the molecular absorbing gas and with the beam to encode position information as a function of the specific frequencies. The amplitude of the first encoding frequency varies from a maximum at one edge of the beam, decreasing to a minimum at the opposite edge, and vice versa for the second encoding frequency. The amplitudes of both are equal on beam center.

Abstract: A wideband optical ring modulator is disclosed. A ring resonator containing a synchronous travelling wave electro-optic modulator is disposed external to a laser cavity. The invention provides a compact lightweight optical modulator which combines the power enhancement capabilities of a resonant cavity with the wideband capabilities of a travelling wave coupling modulator. The present invention is especially useful for, although not limited to, ultra-wideband infrared laser communication systems utilizing PCM techniques.