Abstract: An interference spectroscopy instrument provides simultaneous measurement of specular scattering over multiple wavelengths and angles. The spectroscopy instrument includes an interference microscope illuminated by Koehler illumination and a video camera located to image the back focal plane of the microscope's objective lens while the path-length difference is varied between the reference and object paths. Multichannel Fourier analysis transforms the resultant intensity information into specular reflectivity data as a function of wavelength. This multitude of measured data provides a more sensitive scatterometry tool having superior performance in the measurement of small patterns on semiconductor devices and in measuring overlay on such devices.

Abstract: A Mireau interference microscope is corrected for spherical and other aberrations induced by the beamsplitter and mirror support windows by incorporating a cover glass correcting-objective lens. The support windows for the beamsplitter and mirror have a combined thickness within the adjustment range of the cover glass correcting-objective lens.

Abstract: A family of controllers incorporate multiple force/touch sensitive input elements to provide intuitive input in up to six degrees of freedom, including position and rotation, in either a Cartesian, cylindrical or spherical coordinate system. Six dimensions of input can be generated without requiring movement of the controller, which provides a controller suitable for controlling cursors and display objects in an interactive computer system and for equipment such as heavy cranes and fork lift trucks. Positional information is obtained either by use of a "pushing" or "dragging" metaphor. Rotational information is provided by either a "pushing," "twisting," or "gesture" metaphor. In certain embodiments, the same sensor is used for both positional and rotational inputs, and the two are differentiated by the magnitude of the force applied to the sensor.

Abstract: A broadcast and reception system provides a segmented broadcast signal for providing regional traffic information and a receiver adapted to receive selected segments of that broadcast. The segmented broadcast signal includes a number of segments which each include a tone sequence, a digital regional code, a digital duration code, and an audio segment. The receiver monitors selected regional traffic segments and converts the selected audio segment to a form compatible with a standard automotive radio. Thus, a user can selectively monitor regional traffic information without having to listen to reports from regions of no interest to him. Alternatively, the selected traffic information can automatically override normal radio listening.

Abstract: A raster graphics color palette architecture for multiple display objects or sprites includes a first memory for storing pen index information for each display object. The pen index information for each display object includes pen index information corresponding to each pixel of that display object. A second memory stores indexing information for each display object. The indexing information maps the pen index information for the corresponding display object to pen numbers. A pen palette device includes a number of dynamically alterable registers, or "pens," containing RGB information for driving a multicolor raster display. In operation, pen index information representing the pixels of a display object is accessed from the first memory. This pen index information is mapped into pen numbers using the indexing information for the display object stored in the second memory. These pen numbers are then coupled to the pen palette to provide the RGB information for driving a multicolor raster display.

Abstract: A construction set is made up of a plurality of detachably chainable links capable of being pivotally attached to one another to form stable geometric structures. Detents are provided at a plurality of pivot positions so as to preferentially hold the engaged links in stable and precise positions relative one to another.

Abstract: A shaft angle encoder adapted for use in a hand-held gyroscope has a motor at the core of the gyroscope suspended by two pairs of orthogonal gimbals to provide two-degrees-of-freedom for the inner gimbal. Power is provided to the motor through conductive elements in the bearings without limting the range of motion of the gyroscope. An electro-optical shaft angle encoder for detecting the rotation of the inner gimbal with respect to the outer gimbal includes an optical pattern mounted along a cylindrical portion of the inner gimbal about the axis of rotation of the inner gimbal and in alignment with one of the outer gimbal bearings. A light source and a rotational phase plate are mounted to the outer gimbal and aligned with this optical pattern and a light path is provided through the optical pattern, the rotational phase plate, and the outer gimbal bearing.

Abstract: A system (60) for predicting CPU addresses includes a CPU (34) connected by bus (62) to page mode address predicting circuit (64). The page mode address predicting circuit (64) is connected to memory arbitration circuits (66) by bus (68). The memory arbitration circuits (66) are connected to RAM (42) by address, data and control busses (44), (46) and (48). The CPU (34), page mode address predicting circuit (64) and the memory arbitration circuits 66 are contained in a microprocessor integrated circuit (32). The page mode predicting circuit 64 examines signals from the CPU (34) to be supplied to the data bus (46) at the time of a SYNC pulse. This operation results in examination of the first byte of a CPU instruction to determine how many of the following memory accesses will be able to be carried out in high speed mode.

Abstract: A multi-directional switch assembly, such as a joypad or joystick for an electronic game apparatus, including a printed circuit board, a resiliently deformable member having contact elements thereon and an input member mounted to deform the deformable member to effect closing of the switches. The input member is pivotally mounted by a post assembly, and the post assembly is supported by the game apparatus housing in a manner which is independent of the printed circuit board to substantially isolate the printed circuit board from thrust forces manually applied to the joypad input member.

Abstract: A method and circuit generate a dependent clock signal from a master clock signal with minimal skew of the dependent clock signal with respect to the master clock signal and inverting it to create a second master clock signal that is one hundred eighty degrees out of phase with the first master clock signal. The second master clock signal is used to drive a flip flop type circuit so that the flip flop circuit changes states when the first master clock signal is at a "zero" level and the second master clock signal is at a "one " level. The output of the flip flop circuit is enabled using the first master clock signal. Connected to the output of the tri-state driver is a repeater circuit of the type having an output that remains the same as the input until the input level is changed.

Abstract: An electronic musical instrument shaped like an electric guitar sounds individual notes that are synthesized to sound like an electric guitar. These notes may either be selected randomly selected by a player or from segments of prearranged musical tracks. The instrument provides for maintaining the tempo of manually played or preprogrammed notes, synchronizing the transitions between sequentially selected musical tracks, overlaying manual notes on the tracks, and a number of electric guitar-like sound effects including vibrato, chorus, overdrive, slurs and soft picks.

Abstract: An invertible, hand-held, electronic game apparatus having a manually engageable housing, a display screen mounting in the housing, an electronic circuit electrically connected to drive the display screen, and a control switch assembly mounted for manipulation by at least one hand of the player while holding the housing. The control switch assembly includes a joypad and fire buttons which are positioned on the housing to permit rotation or inverting of the housing and operation of the switches in a rotated position. Inversion of the housing and operation of the switches is possible when the images are vertically or horizontally oriented. In the preferred form, the control switch assembly includes a joypad on one side of the display screen and two pairs of functionally duplicate fire buttons symmetrically positioned about a central plane of the housing on an opposite side of the screen. The back of the housing is formed with protruding convex surfaces to facilitate gripping.

Abstract: A speedometer is provided for determining speed by providing a sound signal at a first frequency, receiving a second signal which is the reflection of the first signal, and determining difference in frequency between the first and second signals created by the Doppler Effect. A speech synthesis chip within the speedometer provides a verbal indication of velocity. In this way, a person using the provided speedometer does not have to look at a dial or other visual indicator.Provided within the speedometer is a heat-sensitive transducer for measuring the air temperature. In this way, the speedometer can take into account the change in the speed of sound with respect to temperature when calculating velocity.

Abstract: A three-dimensional ultrasonic position control device suitable for controlling computer displays or robot movements is disclosed.More specifically, signals from an ultrasonic transmitter are received by multiple receivers. The received signals are processed by a processing circuit which provides signals to a computer system for use in controlling a computer display or a robot. This system is particularly adapted to use inexpensive components to provide for a low cost mass producible control device.

Abstract: A triggerable oscilloscope having a digital clock selectably connected to two digital counters accurately measures a time interval between two recurring events. The first digital counter is connected to the digital clock to count clock pulses during a timer interval between the initiation of a horizontal sweep signal and the occurrence of the first recurring event. A second digital counter is connected to the digital clock to count clock pulses during a time interval between the initiation of a sequent horizontal sweep signal and the occurrence of the second recurring event. A subtractor circuit coupled to the first and second digital counters subtracts the count of the first digital counter from the count of the second digital counter and determines the time interval between the first and second recurring events.Time averaging techniques increase the accuracy of the time interval measurements for high speed recurring events by accumulating counts during a plurality of horizontal sweep signals.

Abstract: A proportional oven having two heaters mounted to a thermally conductive base stabilizes the temperature of a temperature sensitive crystal mounted on the thermally conductive base by adjusting the ratio of powers applied to the two heaters.

Abstract: An optical comparator has three bifurcated and truncated lenses, each lens having two siamesed and truncated elements having closely spaced optical axes. This results in an optical encoder having a low sensitivity to eccentricity errors.

Abstract: A three-channel optical shaft angle encoder has two channels for encoding the incremental angle and the direction of rotation of a shaft. A third channel provides a synchronizing index pulse for encoding the absolute position of the shaft once per revolution. The encoder has an emitter module containing three high irradiance LED emitters and integral truncated collimating lenses for producing three closely spaced collimated light beams, one beam for each channel. These light beams are modulated as a function of the relative angle between a code wheel coupled to the shaft and a phase plate fixedly mounted to the body of the encoder. The modulated light beams are received by a detector module having beam splitting truncated and siamesed lenses positioned to split each of the closely spaced light beams and to focus each of the split beams onto a photo detector pair.

Abstract: A general purpose logic state analyzer selectively stores, formats and displays a digital signal representing a sequence of data states input thereto and provides a graphical display of the stored data states and a count of selected events occurring intermediate to the occurrence of the data states stored. Selective storage of the input data states is provided by comparing the input data states to a preselected sequence of first qualifier state conditions and enabling the storage of input data states in response to the satisfaction of the preselected sequence. Storage is further qualified by storing only data states which individually meet one of a preselected set of second qualifier state conditions.