Abstract: A socket for testing integrated circuit has opposite cantilever probing pads hinged at the far ends of the cantilevers to a circuit board. The leads of the IC are pressed over the free nearer ends of the cantilevers. Cushions are inserted under the two free nearer ends of the cantilevers to absorb in the pressure of the IC leads. For in-line lead IC packages, a common cushion can be used for each line of leads. Metallic pedestals can be mounted on the between the nearer ends of the cantilever and touching the IC under test for heat sinking and common ground. The pedestals can be inserted through the circuit board from a base plate at the bottom of the circuit board.

Abstract: A MOSFET can operate as a resistor by operating in the linear or ohmic region of the drain V-I characteristics. This region can be obtained by floating the gate of the MOSFET, when the dc current and the voltage drop are given. Multiple resistors can be duplicated (or mirrored) by sharing the same source and floating gate. The floating gate voltage can be simulated using a closed loop equivalent circuit. Alternatively, the gate voltage can also be derived from the given drain-to-source voltage and the given current in a feedback loop. With this adaptive MOSFET resistor, the minimum supply voltage can be as low as the sum of the BJT threshold and the complementary BJT saturation voltage, e.g. VCC?VBE+Vsat (e.g. 0.8+0.15<1.0V). The threshold voltage Vt should be less than VBE.

Abstract: Invisible different monochromatic images are inscribed in a diffractive optical element. Each of the images appears when a specific light source is on and image disappears when the specific light is off. The light sources for the different monochromatic images are spaced at different positions with respect to the diffractive optical element. A dynamic image is produced by time-varying and electronically controlling the intensity and on/off of the different light sources.

Abstract: A flat bed image scanner uses a contact image sensor to scan a document. The distance between the contact image sensor and the glass window, over which the document is placed, is minimized and held constant by inserting a lubricating element between the contact image sensor and the glass window. The lubricating element may comprise two pads placed at the two ends of the contact image sensor. The lubricating element can also be integrated structurally with the contact image sensor. The material of the lubricating element can be nylon or some other kinds of plastic. The lubricating element may also comprise two guide rails placed at the two edges of the scan window.

Abstract: This invention discloses novel device structures for fill color flat panel displays utilizing pseudomorphically cladded quantum dot nanocrystals. Different colors are obtained by changing the core size and composition of the quantum dots while maintaining a nearly defect-free lattice at the core-cladding interface. Light emission from the quantum dot core is obtained either by injection or by avalanche electroluminescence. A nanotip emitter device is also presented. These generic devices can be addressed using a variety of conventional display drivers, including active and passive matrix configuration.

Abstract: An array of light emitting diodes (LED) are laid out as a dot matrix array as a display panel. Each LED is accessed by two dimensional addressing from a first set of parallel horizontal interconnections and a second set of orthogonal interconnections. The two sets of orthogonal interconnections are printed on two sides of a substrate. One of the two electrodes of an LED, which mounted on the top of the substrate, is fed through the substrate with a via hole and connected to the orthogonal interconnection at the bottom of the substrate. The size of the display panel is configurable by removing certain rows and/or columns. More than one partitioned blocks can be pieced together by aligning and coupling the corresponding orthogonal interconnections through a motherboard.

Abstract: An integrated circuit chip with ball-grid array solder balls is packaged as a module without being sealed in protective glue. The IC chip is mounted on an insulating substrate with pads to support the solder balls. The pads are connected to a second set of pads along the periphery of the substrate. Leads are pressed against the second set of pads for external connections. A second IC chip may be pressed against the other side of the substrate to increase the external connections.

Abstract: A BJT operating as a mixer has its collector biased at the knee of the IC vs VCE characteristic. A local oscillator voltage is applied to the base and an RF signal voltage is applied to the collector through a singled-ended emitter follower. The nonlinear curvature at the knee produces a beat frequency current. The base of the emitter follower can be fed from a current mirror or through an ohmic resistor. This mixer requires less supply voltage, and results in more conversion gain and less feed-through of the RF input signal than the Gilbert multiplier. Alternatively, the RF voltage can be applied to the gate and the local oscillator voltage can be applied to the drain. Sometimes, it is more desirable to invert the collector and the emitter, or to connect a normal transistor and an inverted transistor in parallel to optimize conversion gain.

Abstract: A replaceable friction roller is mounted on the driving shaft of a paper conveying roller. The roller is made replaceable by providing a slit from the surface of the roller to the shaft surface. The roller can be split open along the cur when replacing a new roller. The ends of the shaft of the roller are inserted in at least one open mouth socket. The socket has spring action to hold the shaft in place.

Abstract: One or more UV light emitting diode (LED) chip is used as the light source of a picture projection system. The UV LED light is converted into red, green and blue light beams by means of red, green and blue fluorescent plates, respectively. The lights emerging from said fluorescent plates is transmitted through one or more programmable liquid crystal plate or reflected by one or more digital micro-mirror device (DMD) to control the light transmission, and then merged together for projection onto a screen. When only one programmable liquid plate or one DMD is used, the different color signals are sequentially projected onto the screen.

Abstract: The light emitted from a bank of light emitting diodes is converted through a set of lenses into parallel light beams, which, in turn, is focused or diversified as projection light source. Such a light source can replace traditional incandescent bulb. Reflection mirrors can be used to deflect or reflect the light beams. Phosphorescent material can be added in the transmission path to convert blue or ultraviolet short wave light into white light.

Abstract: One or more LED panel is used as a light source of a light projector. The LEDs are mounted on a panel and arranged as a matrix array. The light emitted from the LEDs are reflected by a reflecting cup. The LEDs are connected to two separate metal parts each connected the two electrodes of the LEDs. The spaces between the LEDs are utilized for light passage.

Abstract: Through-holes are inserted in the substrate of an LED matrix to increase air circulation and cooling. Fans may be used to increase cooling.

Abstract: The surface of the glass window of a scanner is coplanar with flanges on top of the scanner frame. The light path between the scan window and the light sensor mounted on the frame is prevented from varying regardless of any interface tolerance in mechanical dimension of the optical components in the light path between the scan window and the light sensor.

Abstract: Two optical modules with reflecting mirrors provide two moving speeds so as to maintain a constant light path between the scanned image and the image sensor. One of the optical modules, the first module, is mounted with two driving wheels. One driving wheel rubs against a stretched belt to move the first module in one direction. The second driving wheel pulls the second optical module toward or away from the first optical module by means of a second belt which is connected to two sides of the second optical module and loops around the second driving wheel. When the two driving wheels rotate in the same direction, the second optical module moves a half as fast as the first optical module. When the two driving wheels rotate in opposite direction, the second optical module moves twice as fast as the first optical module. Thus, two different moving speeds of the modules are achieved.

Abstract: An LED display panel are mounted with an array of LEDs on a number of metallic partitions, serving as common electrodes foil a line of LEDs as well as heat sinks. Another number of rails serve as common electrodes for another line of LEDs. The metallic partitions and the rails are orthogonal to and insulated from one another at their cross-points.

Abstract: LEDs of a light matrix display are mounted between two metal frames. Each frame has air ducts to circulate air around the LEDs, thereby removing the heat generated in the LEDs and allowing higher intensity light to be emitted.

Abstract: The paper guide for a scanner has an upper guide and two lower guides: the inlet lower guide and the outlet lower guide. The inlet lower guide overhangs over an output lower guide and is separated by a gap in the direction of the paper movement. The paper is scanned at the gap by the scanning light.

Abstract: Surface mount diodes are mass produced by first cutting a metal plate to form a plurality of vertical slits within metal plate. Parallel lines are cut midway between the slits to form wings for the slits. The wings are folded to form the bottoms for surface mounting. Glue is applied over the metal plate to form focusing cups.

Abstract: The VCO of a synthesizer operates with a coarse tuning and a fine tuning. During the coarse tuning, a binary search method is used to match the VCO frequency to one of a finite number of discrete reference frequencies. The coarse tuning operates without frequency division and phase comparison in a closed feedback loop, thereby speeding up the settling time and increasing the lock-in range. The fine tuning operates as a conventional analog PLL.