Abstract: A technique is disclosed which facilitates the selection by a user of a graphic object on a display screen. Selection is by means of a pointing cursor which is moved about the display screen by means of a pointing device having a select button. When the pointing cursor is brought within a predetermined distance of a graphic object, the point on the graphic object closest to the pointing cursor is highlighted to show the user that that graphic object would be selected if the select button were pressed. If the user presses the select button when a point on a graphic object is highlighted, the entire graphic object is highlighted to indicate that it has been selected.

Abstract: An apparatus capable of sensing sudden approach of a succeeding vehicle and emitting an alarm, while being free from malfunction that may otherwise be caused by the noise from the succeeding vehicle which has approached at a normal speed and stopped in the proximity.

Abstract: An X-Y signal generator comprising a guide block having parallel cylindrical guide surfaces at opposite edges of the block, and a sleeve closely fitting about the block and riding on those surfaces. A planar window area is arranged close to the sleeve along a flat face of the block, with an identifiable actuating part of the sleeve appearing within the window. Finger pressure on the actuating part permits finger movement and direction parallel to the cylindrical surfaces to slide the sleeve in that direction, and finger movement in the orthogonal direction rotates the sleeve about the cylindrical surfaces. Movement of a surface of the sleeve, preferably at the opposite side of the block from the window, is sensed to provide electrical signals corresponding to the direction and distance of movement. Preferably, light gratings aligned in each of the two directions are formed directly on the sleeve.

Abstract: A matrix-addressed display device having a cursor which is movable independently of the displayed information is disclosed. Two interrupt circuits are used to override or interrupt the refresh cycling of the displayed information and to relocate the cursor in the display device in response to a user input control such as a keyboard, joy stick or the like. One interrupt circuit comprises a pair of AND gates and an inverter, while the other interrupt circuit comprises a plurality of AND gate pairs with each pair having an inverter. The interrupt circuits enable the cursor to be moved to its new location prior to completion of the refresh cycling of the displayed information.

Abstract: The present system includes an optical reflective sensor, which is hand held and moved over a color density scaled grid, such as a gray scale grid, to produce analog signals which, when processed, become the basis for the direction of movement of a screen cursor. The analog signals are converted into binary coded signals and further into hexadecimal signals. Each hexadecimal signal is transmitted to eight AND gates whose other inputs represent a (gray scaled) value of a position from where the sensor could have been moved. Accordingly only one AND gate will produce an output signal and that output signal will only be produced if the move is a valid, or acceptable, move. If the sensor has been validly moved, the output signal of the selected AND gate will be interpreted (circuit-wise) to represent one of the directions of a compass. The output signal will be used to change the state of a bit map memory to thus move the screen cursor. Hence the screen cursor will follow the sensor.

Abstract: An image registration system for registering multiple images on a screen is disclosed. A registration pattern is projected on the screen along with the image to be registered and in a fixed position in that image. A sensor apparatus for each image, having three photodetectors disposed in a right angle relationship is mounted on the screen at a predetermined location for determining the position of the registration pattern on the screen. The position of the registration pattern on the screen is determined by comparing the outputs of the three photodetectors. Difference signals are produced by the comparisons and are used to reposition the projected image to bring it into registration. The sensor apparatus are disposed so that when the registration patterns are in register with them, the images are in register with each other.

Abstract: Disclosed is an apparatus and method for controlling the cursor of a computer display. The apparatus includes a headset which is worn by the computer operator and an ultrasonic transmitter for transmitting sound waves which are picked up by the receivers in the headset. These sound waves are compared for phase changes, and circuitry is provided for converting the phase changes into position change data which is used by a computer to control the cursor.

Abstract: A multipurpose keyswitch for controlling cursor movement on a CRT display and for character entry includes a key cap that moves laterally to provide cursor control and that moves vertically for character entry. Sensors are coupled to the key cap for sensing the lateral movement of the key cap. Forward and backward movement of the key cap selects upward and downward movement of the cursor on the CRT display. Left and right movement of the key cap selects left and right movement of the cursor. Vertical movement of the key cap selects the entry of a character. The multipurpose keyswitch is advantageously positioned as one of the home keys of the keyboard.

Abstract: A cursor controller has a handle having first and second perpendicular slots disposed in different parallel planes. A first cross-slide is slidably mounted in the first slot and guides the motion of the handle along an x axis. A second cross-slide is slidably mounted in the second slot and guides the motion of the handle along a y axis. A first encoder strip mounted to the first cross-slide is provided together with a quadrature detector for sensing the direction and magnitude of movement of the handle along the y axis. A second encoder strip mounted to the second cross-slide is provided together with a quadrature detector for sensing the direction and magnitude of movement of the handle along the x axis. Signals from the quadrature detectors are processed and coupled to a computer to provide cursor control on the computer's display screen.

Abstract: A display arrangement for a head-up display system e.g. for an aircraft, wherein the combiner (13) comprises a first tuned reflective optical film (39) through which an observer (14) views a distant scene and second and third tuned reflective optical films (41 and 43) positioned outside the observer's view of the distant scene through the first film. Light from a projector (11) passes first through the nearer (43) of the second and third films, is then reflected at the other (41) of the second and third films, is then reflected at the nearer film (43) and then passes through the other film (41) to the first film (39) where it is reflected towards the observer. The three films are normally designed to provide the combiner with a desired optical power, the one (43) of the second and third films nearer the projector suitably being concave toward the other (41) of the second and third films for this purpose.

Abstract: Lantern employs clear lens protective cover around the drum lens and a clear dome over the solar panel mounted above the lens. A heavily damped gimbal supported by the lantern housing mounts the lens, lampchanger, and flasher above a bank of batteries suspended from the gimbal. The weight of the batteries aids in providing a righting moment to the gimbal when the marine buoy, atop of which the lantern is secured, is tilted or inclined for sustained periods due to current and/or wind. Interior of the lantern is readily accessible by merely pivoting upwardly an annulus supporting the lens cover, solar panel, and dome.