Abstract: A photometric skin condition analyzer is provided which exploits the light refraction and Rayleigh scattering from small particles, such as droplets of oil, deposited on optically smooth sampling surfaces of a sampling pellet. Light emitted from an optical source is passed through the sampling surface and focused onto an optical detector. The output signal of the detector is displayed to give an indication of the degree of oiliness of the skin.

Abstract: A method of making an electron permeable window is provided which entails depositing a thin film of an inert, high strength material or compound having a low atomic number onto a substrate by chemical vapor deposition (CVD). Following that deposition, a window pattern and window support perimeter are photolithographically defined and the substrate is etched to leave the desired window structure. For a particular class of materials including SiC, BN, B.sub.4 C, Si.sub.3 N.sub.4, and Al.sub.4 C.sub.3, films are provided which are exceedingly tough and pinhole free, and which exhibit nearly zero internal stress. Furthermore, due to their extreme strength, these materials allow fabrication of extremely thin windows. In addition, because of their low atomic number and density, they have excellent electron penetration characteristics at low beam voltages (15 to 30kV), so that most conventional CRT deflection schemes can be used to direct the beam.

Abstract: A thermal ink jet printer is disclosed in which ink droplets are ejected from an orifice by the explosive formation of a vapor bubble within the ink supply due to the application of a two part electrical pulse to a resistor within the ink supply. The electrical pulse comprises a precurser pulse and a nucleation pulse; the precurser pulse preheats the ink in the vicinity of the resistor to a temperature below the boiling temperature of the ink so as to preheat the ink while avoiding vapor bubble nucleation within the ink supply and the subsequently occuring nucleation pulse very quickly heats the resistor to near the superheat limit of the ink.

Abstract: An apparatus is disclosed for propelling ink droplets from an ink jet nozzle which uses an expanding bubble as a driving mechanism. Unlike other thermal ink jet devices, the ink itself is not used to provide the driving bubble. Rather a two fluid system is disclosed whereby a flexible membrane is used to maintain separation between a working fluid and the ink. A bubble is thermally created in the working fluid which distends the membrane and causes ink on the other side of the membrane to be expelled from an ink jet orifice. The membrane is in direct physical contact with the surface of the bubble-generating resistor and a quantity of the working fluid lies between the resistor and the membrane in pockets created by roughening the surface of the membrane or by roughening the surface of the resistor; alternatively, pockets between the membrane and the resistor may be provided by particulates contained within the working fluid which provide local separations of the membrane and the resistor.

Abstract: A reflecting telescope is provided in which a meniscus lens corrects for coma of the primary parabolic reflecting mirror, and also for coma and spherical aberration of an eyepiece, when an eyepiece is used. The meniscus lens may be formed from a plano-concave lens and a plano-convex lens positioned with their planar sides mutually parallel.

Abstract: A method of making an electron permeable window is provided which entails depositing a thin film of an inert, high strength material or compound having a low atomic number onto a substrate by chemical vapor deposition (CVD). Following that deposition, a window pattern and window support perimeter are photolithographically defined and the substrate is etched to leave the desired window structure. For a particular class of materials including SiC, BN, B.sub.4 C, Si.sub.3 N.sub.4, and Al.sub.4 C.sub.3, films are provided which are exceedingly tough and pinhole free, and which exhibit nearly zero internal stress. Furthermore, due to their extreme strength, these materials allow fabrication of extremely thin windows. In addition, because of their low atomic number and density, they have excellent electron penetration characteristics at low beam voltages (15 to 30 kV), so that most conventional CRT deflection schemes can be used to direct the beam.

Abstract: A new type of thermal ink jet print head is provided which is driven by an electron beam. The print head is constructed of an electron permeable thin film (electron window) which in one embodiment, has on one of its surfaces a plurality of electron absorbing (heater) pads that are in thermal contact with an ink reservoir. As electrons from a CRT traverse the thin film and are absorbed by a pad, they introduce an extremely large and rapid temperature increase in the pad. As a result, a sufficient amount of thermal energy is absorbed by the ink to cause a vapor explosion within the ink, thereby ejecting ink droplets from a nearby orifice in the ink reservoir. In another embodiment, the electrons traverse the window and are absorbed in the ink rather than in pads, and in another embodiment the electrons are absorbed directly in the window itself.

Abstract: An electron beam blanker for use in electron beam lithography systems is disclosed which is capable of providing exposure rates on the order of 300MHz at beam currents of approximately 600nA. A condensing lens and a stigmator are provided to bring the electron beam to a small image in a plane perpendicular to the beam direction. An etched silicon knife-edge, coated with gold, is located in this image plane in close proximity to the beam, to provide a sharp cut-off as the beam is swept past its edge. In accordance with aspects of the invention, a deflector plate structure provides an electromagnetic field whose geometry ensures that the velocity of a beam electron, as it exits the field, is substantially directly proportional to the undeflected beam electron's position vector relative to the beam cross-over in the image plane of the condenser lens.

Abstract: A method of making a monolithic bubble-driven ink jet print head is provided which eliminates the need for using glue or other adhesives to construct multiple part assemblies. The concept of the method is to provide a layered structure which can be manufactured by relatively standard integrated circuit and printed circuit processing techniques. First, a substrate/resistor combination is manufactured. Then a foundation of conductive material is firmly attached to the substrate and a resist layer is used to define a perimeter/wall combination over the foundation, with the perimeter/wall combination surrounding the resistors and providing hydraulic separation between them. The perimeter/wall combination is then electroplated in place. A flash coat of metal is applied over the resist which is inside the perimeter of the perimeter/wall combination and a second layer of resist is used to define the desired orifices and the external shape of the part.

Abstract: A high-speed print hammer and magnetic actuator is provided which operates with a minimum of power dissipation, can achieve high speed, and has very little flux leakage beyond the mechanical structure. The magnetic actuator is made up of two pole pieces having a high magnetic permeability, with a permanent magnet therebetween. A print hammer, also having a portion constructed of a material with a high magnetic susceptiblity, is pulled away from its unsprung position by the permanent magnet and contacts the faces of the pole pieces, providing a very low reluctance magnetic path between them. The print hammer is released from this cocked position by a pulsed electromagnetic field applied in a direction opposite that of the permanent magnet, the pulse pattern corresponding to the desired impact pattern of the print hammer.

Abstract: A bi-directional pen changer for use in an X-Y plotter is disclosed which requires only a single axis of motion for pen snatch, pen re-insertion, and plotting. The device is made up of two pen stables, one on each side of a pen carriage, for holding pens when not in use, and a pen holder located between the two pen stables which holds a pen during plotting. The pen holder is mounted on the pen carriage and is a symmetric device configured to snatch and re-insert a pen from either side. The snatch and re-insertion of pens by the pen holder is accomplished by co-acting clamp arms on the pen holder and on each pen stable. The pen holder clamp arms are configured such that the pen tip is always at the same location relative to the clamp arms when the pen holder is holding a pen, regardless of the side from which the pen is snatched.

Abstract: A pulse generator circuit generates pulses or logic signals with variable upper and lower levels. According to a preferred embodiment of this invention there are provided two variable voltage sources representing variable logic state levels. For alternately connecting these voltage sources with the output of the circuit there is provided a diode bridge in the configuration of a Graetz rectifier with two nodes connected to these voltages sources and the other two nodes forming complementary output signals; these latter two nodes are also connected to equal and opposite constant current sources which are reversible in accordance with a control signal. The voltage sources are coupled to the bridge via operational amplifiers configured as voltage followers. In each associated feedback loop of the voltage sources there is a diode substantially identical to those of the bridge which is coupled to a constant current source equal in magnitude to those of the constant current sources connected to the bridge.

Abstract: An optical erasable liquid crystal disc memory system is provided which includes a rotating liquid crystal information storage medium confined by two surfaces. Various thin films on the surfaces are used to establish the proper conditions within the liquid crystal medium which, in combination with incident radition and applied voltages, accomplish the read, write, and erase functions.The resulting system provides a locally erasable optical disc memory with high density storage, long-term information stability under a wide range of temperature, and read, write, and erase times compatible with modern high speed computers.

Abstract: An optical erasable thermally addressed, liquid crystal information storage and retrieval system is disclosed having an information density and the order of 10.sup.7 bits/cm.sup.2 while using liquid crystal cell thickness of relatively standard dimensions (.about.10 .mu.m). The system includes two substrates containing a smectic-A phase liquid crystal medium, and several thin filing attached to the substrates for establishing the proper conditions within the liquid crystal medium for creating a radiation scattering defect which is small in size (<1.0 .mu.m), and for performing erase functions in conjunction with an optical beam. A device according to the invention has an array of such defects in the liquid crystal medium representing information bits, with the array having a ratio of the shortest distance between individual defects to the thickness of the liquid crystal medium of less than 0.4, for a liquid crystal medium having thickness larger than 5 microns.

Abstract: A moving-medium XY plotter is provided with a platen which has a concave surface extending uniformly in the direction of pen motion. A drive roller and pinch roller assembly located near the bottom of the concavity provides the motion of the recording medium orthogonal to the pen motion, while at the same time curving the recording medium into the shape of a trough. This curvature stabilizes the motion of the recording medium by significantly enhancing its resistance to compressional buckling and ensures that the recording medium, as a result of its natural stiffness, will firmly contact the platen where writing is to occur.