Abstract: Apparatus for and a method of optical inspection in a total internal reflection holographic imaging system. Multi wavelength laser beams are directed onto a prism supporting a first substrate containing pre-recorded hologram which is to be imaged onto a recording medium of a second substrate, the multi wavelength beams being normal to both substrates. The distance between the two substrates is measured by interferometric techniques. Actuators are provided for adjusting the distance between the two substrates, these actuators being energized to cause minute adjustments of the spacing during a scanning operation whereby the imaging of the pre-recorded hologram is ensured at the correct focus throughout the scanning operation.

Abstract: Access authorization is validated for an information processing system wherein a "slave device" such as a terminal desires access to information contained in or controlled by a "master device" such as a computer. Apparatus associated with the slave device receives validation data from the master device, modifies it according to a pre-determined algorithm implemented through logical circuitry in the apparatus, and returns the resulting "convoluted" data to the master device. The same validation data is convoluted in the master device through mathematical implementation of the algorithm. If the two sets of convoluted data match, it is presumed that the slave device is authorized to access information through the master device.

Abstract: The disclosed method and means measure the characteristics of an optical device by directing light waves by normal-incidence sub-aperture interferometry on the optical device, shear-polarizing the light directed onto the optical device, and analyzing the results of the interference to obtain the characteristics of the optical device

Abstract: An optical head device for projecting a light beam on a recording medium to record data thereon or reproduce the recorded data comprises an optical system for forming a beam spot of a specified diameter on the surface of the recording medium, and a transparent contact member disposed at a light emanating portion of the system for the recording medium to come into direct sliding contact therewith. Accordingly, when the contact member moves relative to the recording medium, the dust adhering to the surface of medium is removed by the contact member to assure a recording or reproduction operation free of errors.

Abstract: A gas laser of the excimer type in which an open waveguide is employed, in which the excimer medium is moved to and through the open waveguide in a direction transverse to the optical axis. A discharge cell is defined by the upper and lower slabs of the open waveguide, and if desired, a microwave source is provided which supplies microwave energy to the discharge cell volume to excite the excimer medium and to initiate discharge.

Abstract: A micro-step drive system of a five-phase stepping motor is disclosed. When Io is a constant, a unit time interval is 1, a remainder obtained by a time variable divided by 10 is t and an arbitrary constant is .alpha. (0.ltoreq..alpha.<10), each of five-phase windings for a salient-pole corresponding to a k-th phase (k=0, 1, 2, 3 and 4) is supplied with a current I.sub.k. This winding current is obtained by pulse width modulating an output of a constant current converter by an output signal of a pulse width modulation pattern generator and supplying the modulated current to each of the windings as an output of an inverter. A power circuit of the inverter is simplified greatly.

Abstract: A battery charging apparatus includes a charger to which a battery to be charged is loaded and a charge controller which controls a charge in the charger. A terminal voltage of the battery loaded in the charger is sampled and A/D converted by a microcomputer of the charge controller at time intervals. At every timing when a new sampled value is stored in a memory, the new sampled value is compared with a maximum sampled value which has been stored in the memory before that time. When the new sampled value is smaller than the maximum sampled value by a predetermined value (.DELTA.V), a full-charge signal is outputted. In addition, when a state where the new sampled value is larger than the maximum sampled value continues for a predetermined time period or more, the maximum sampled value is updated.

Abstract: A track search circuit includes a command decoder which decodes command data sent by a microcomputer and stored in a command register and outputs signals commanding a track jump and commanding count of a counter which counts a tracking error signal. Time difference between a present A-time and a target A-time is calculated such that an optical pick-up can be moved toward a target position by utilizing the track jump of 4.sup.n. When a counted value of the counter reaches a predetermined value, the A-time is renewed such that the time difference can be reduced by addition or subtraction suitable time data to or from the A-time. If the renewed A-time becomes within 1 minute with respect to the target A-time in repeating such a track jump in accordance with the renewed A-time, the optical pick-up is stopped to move, and the A-time is read to jump the optical pick-up again to catch the target position.