Abstract: A stop for an instrument focusing shaft wherewith the extent of its rotational excursion in one direction may be readily adjusted and repeated. A gear fixed to the focusing shaft and in mesh with additional gearing is selectively stopped by another gear caused to mesh across two gears of the system. The stop gear may be carried out of mesh by reverse rotation of the focusing shaft.
Abstract: A short fiber optic image transmitter receives an image produced by a fiberscope objective and transmits the image to the image receiving end of the flexible fiber optic bundle of the fiberscope. The short image transmitter is oscillated about an axis normal to its direction of image transmission for causing images transmitted thereby to scan across the image receiving end of the fiberscope bundle. Synchronous scanning of the opposite image emitting end of the fiberscope bundle renders the received images stationary and of enhanced resolution.
Abstract: Glass lenses or lens blanks, containing all the ingredients necessary to produce phototropic or photochromic behavior, are treated in a conventional production furnace to produce a locally variable heat treatment, wherein at least one portion thereof is raised to a temperature exceeding the glass strain point but not the softening point, and other portions are heated to variable temperatures decreasing from the strain point. The treatment causes development of phototropic or photochromic behavior only in those portions of the lenses or lens blanks exposed to the temperature above the strain point.
Abstract: Providing visual means for indicating when vapor/gas respirator cartridges have exhausted their capacity to provide respiratory protection at or below a hazardous concentration level. In combination with a vapor/gas indicator adapted to undergo a change in color with contact by an organic vapor or gas, there is provided a catalytic agent for enhancing activation and reaction of the indicator agent.
Abstract: An improved method and apparatus for determining blood pressure in a system employing a variable pressure cuff and having means for sensing a quantity comprising the sum of applied cuff pressure and a component representative of pulsatile pressure in a blood vessel, a particular time derivative of at least the fluctuating component of the quantity is obtained and utilized for determining blood pressure. More specifically, the particular time derivative comprises the second (or greater) derivative and it is analyzed to determine at what applied pressure it first and last crosses a negative threshold value, those pressures then being indicated as diastolic and systolic pressure depending on whether applied pressure is increased or decreased. The threshold value may be dynamically determined.
Abstract: A lens suitable for implantation in the eye is provided with laterally extending iris clips each having at least one of its ends locked within the body of the lens. The clips are initially extended through close-fitting openings, terminally beaded and forcefully retracted sufficiently to bury their beaded ends within the lens body. Cold flow of lens material around the beaded ends locks the clips in place.
Abstract: A method of treating ophthalmic quality lenses or lens blanks that produces a reversible progressive local variation in phototropic behavior with a continuous variation in transmissivity. The lens or lens blank is composed of a potentially phototropic glass containing all the necessary ingredients including uniformly dispersed silver halide particles therein to develop a phototropic behavior during the heat treatment of the present method. The steps of the present method include mounting the lens or lens blank in carrier means, heating the lens or lens blank thus mounted in a heat treatment furnace at a temperature sufficient to develop the phototropic behavior of the potentially phototropic glass. Characteristically the required heat treatment temperature to develop this phototropic behavior is one which exceeds the strain point of the glass but not the softening point thereof.
Abstract: In cardiac signal processing apparatus, there is provided improved means for suppressing pacer signal artifacts, including both the discharge pulse and the recharge waveform (tail) of such artifact. Rate-limiting circuitry is used to substantially suppress the discharge pulse. However additional circuitry responsive to the detection of a pacer pulse is operative to obtain a measure of the electrical discharge of the discharge portion of the respective pacer pulse and to use such measure to generate a tail suppression signal which, when added to the original signal, substantially cancels the original pacer tail.A feed-back loop is opened by the rate-limiter when a pacer pulse occurs and in turn permits a large signal to be imposed on a threshold-level-type pacer pulse detector for connecting the large signal (pacer pulse) to a capacitor during the discharge portion of the pacer pulse.
Abstract: A self-aligning and centering tool and tool holder system for lens surfacing apparatus. The tool and holder are provided with readily manually assembled and disassembled interlocking faces for precise automatic rotational alignment and centering or decentering of the tool without affect by wear from the abrading action of surfacing.
Abstract: An improved fast-recovery circuit for ECG amplifiers and the like. The fast-recovery circuit includes threshold responsive circuitry connected in parallel with part of the resistance associated with the integrator in a feedback circuit of the amplifier. The threshold responsive circuitry operates to increase feedback frequency response of the integrator when the normally very low frequency output signal of the amplifier exceeds a certain threshold. The improved circuit prevents the threshold circuitry from responding to pulses or excursions in the output signal of a relatively higher frequency content and which exceed the amplitude threshold for less than a predetermined interval, as for instance caused by pacer spikes, large QRS complexes and the like. Preferably, the improved threshold responsive means comprises transistor means connected across the integrator's resistance and having capacitance means across the base-emitter circuit thereof for inhibiting response to certain short duration signals.
Abstract: A gas or vapor sensing and alarm device in an air purifying respirator for warning the wearer of hazardous levels of gases or vapors penetrating through the respirator cartridge. An exothermic sensor which can be fitted in the cartridge adaptor or facepiece cavity of the respirator monitors the heat evolved during adsorption of the vapor or gas into the sensor's adsorbent and triggers in alarm when the respirator cartridge has reached the end of its service life.
Abstract: Contact lens sterilizer has a timer operating a catch for holding a capsule containing contact lenses in sterilizing solution in a sterilizing position. In this position, the capsule is inclined toward inversion. When the timer releases the catch after a predetermined period of time, the capsule swings to a substantially inverted position. In this position, a catalyst contained in one end of the capsule contacts the sterilizing solution to neutralize the same. Optionally, a lock mechanism prevents removal of the capsule from the sterilizer until neutralization is complete.
Abstract: Producing from a single contact lens casting mold, lenses of a number of different sizes by including in the casting precursor for each lens, a controlled amount of an extractable diluent of low volatility which is extracted after casting to cause the resulting lens to shrink a calculable amount. Variations in amounts are used to produce corresponding variations in sizes of cast and extracted lenses.
Abstract: A simple and compact image enhancement system for industrial and medical fiberscopes including in each case adjacent each of opposite ends of the fiber bundle of a fiberscope, a plane parallel optical image transmitting plate and means for oscillating the plate about an axis normal to the fiber bundle axis. With one plate transmitting optical images to one end of the fiber bundle and the other plate transmitting the images away from the opposite end of the bundle, ultimate image enhancement and bundle blemish suppression is accomplished by synchronous oscillation of the two plates.
Abstract: A lens suitable for implantation in the eye is provided with iris clips formed of plastic filaments each having at least one of its ends fastened to the lens. Ends of the clips to be fastened are ferruled for secure and permanent affixation.
Abstract: In systolic pressure determining apparatus utilizing a pressure cuff and means for measuring a fluctuating quantity proportional to the sum of the cuff pressure and the fluctuating component proportioned to the pulsatile blood pressure, and including means for determining the maximum value of the fluctuating component as cuff pressure is varied, the improvement comprising means for converting the quantity into a representation of a time derivative of the fluctuating component means for obtaining the time integral of the time derivative over an interval of predetermined limits between initiation of systolic rise and systolic peak in each blood pressure pulse, and means extending the time integral, as a measure of pulse pressure amplitude, to the maximum value determining means. Specifically, certain crossings of a reference value by the time derivative are recognized as being the initiation of systolic rise and the systolic peak respectively, and the integration occurs over this interval.