摘要:
A method for fabricating an optical diffraction element or grating, where the spectral response of phase gratings is substantially optimized by introducing structure into the grating groove profile. Spectral range of the grating is extended when compared to conventional blazed gratings.
摘要:
An addressable array of lenses is disclosed. Two electrical connections per row address specific lenses within that row. Carriages support individual lenses, thus forming resonant units with frequencies unique within each row. A voltage, having the same frequency as a selected resonant unit is applied. The selected lens produces a resonating image. Testing has verified proper resonance addressing within a 5-by-5 array of microlenses. The array can be applied to a Shack-Hartmann (SH) sensor. To compensate for errant images formed outside of their image area, resonating images are identified by a processor. The array thus improves the dynamic range of the wavefront aberration that can be measured by an SH sensor. The inventors currently estimate the improvement over conventional designs to be about a factor of 30.
摘要:
An apparatus for balancing bodies of rotation in which the body is mounted for rotation while supported at two points. Two load cells are located at each point for producing an unbalance signal. One load cell at each point is connected to measuring electronics which indicate the amount of unbalance while the other cell is connected to processing electronics which indicate amount and location and transmit a signal to a processing machine.
摘要:
A control arrangement for controlling the power supplied to an electric motor connected to a rotary member to drive same in rotation by way of a belt drive, to accelerate the rotary member to a given speed and to brake it in a slip-free manner provides that a signal which is proportional to the speed of rotation of the rotary member is compared to a signal which is proportional to the speed of rotation of the motor. The supply of power to the electric motor is correspondingly controlled in dependence on the result of the comparison operation.
摘要:
An air cylinder has a main piston which is movable backwardly and forwardly under the control of air pressure and it is closed on at least one end with an axially extending damping bore which terminates in a closed end having a stop member adjacent this end. A vent hole connects to the interior of the cylinder to the damping bore and another vent hole connects into the cylinder main space. Each vent hole is advantageously connected to a throttle and check valve which permits inflow of air to the associated spaces and a throttled exit of the air depending on the position of the piston in the cylinder. The piston carries a damping piston in the form of a cylindrical extension thereof which is movable with the piston toward the closed end and has an open end with an axially extending damping bore therein having a check valve which closes the opening. The damping piston moves with the main piston so that adjacent the end position of movement of the main piston, the damping piston enters into the damping bore so as to bring its end into proximity to the stop which opens the check valve. The effect is to cause a slowing motion of the main piston until the stop reaches the check at which the main piston approaches substantially its end position at which time the remainder of the air trapped ahead of the main piston is exhausted through one or more of the vent holes.
摘要:
A ridged cylinder is fused to a sheet of filter material that extends to form a pouch. When the cylinder is placed into the opening of a vessel of a matched diameter, it creates a barrier via the filter material, through which all materials must pass to reside in the vessel. The mammal's penis is directed to ejaculate into the cylinder, and the ejaculate plug is retained by the filter material, while the semen passes through the filter and into the vessel. When the collection is complete, the cylinder and attached filter material are removed from the vessel and disposed of.
摘要:
A medical instrument for ligation of tissue and anatomical structures, including fallopian tubes comprises at least two slideable shafts concentrically disposed relative to each other. A first shaft has a tissue receiving recess into which tissue is retracted by a grasper. The grasper is disposed on the end of a second shaft that is extendible from the first shaft. A ring retainer on the second or a third shaft can hold one or more elastic rings that are displaceable by the instrument around tissue extending from the tissue receiving recess. The rings are held on a tapered or necked down part of the instrument so that the rings contribute little or nothing to the largest outer diameter (OD) of the portion of the instrument that is inserted into a patient's body. Because the ring or rings do not contribute to the OD of the instrument, the instrument may be constructed to fit within insertion channels of 5 mm or less.
摘要:
An apparatus for measuring an unbalance of a rotary member, such as an electric motor armature, comprises a rotary member mounting arrangement for rotatably mounting the rotary member for a measurment operation. The mounting arrangement is capable of oscillating movement in a measurement direction. A drive belt for driving the rotary member in rotation bears against the rotor in substantially tangential relationship therewith or passes around the rotor over a small part of the periphery thereof. A measurement transducer detects forces or oscillations produced by the rotation of the rotary member in the measurement direction and outputs a corresponding signal for unbalance measurement. The drive direction of the belt drive in relation to the rotary member is normal to the measurement direction. The measurement direction may be inclined to facilitate fitting the rotary member into and removing it from the mounting arrangement of the apparatus.
摘要:
The invention relates to a feed drive for work holders of sewing assemblies, by which, during the formation of the initial stitches of a seam taking place at a low speed, the control cam plate moving the work holder is driven at a reduced speed, and, during the formation of the main part of the seam taking place at a high sewing speed, the control cam plate is driven intermittently in a manner such that at every lowermost position of the needle, the work holder is temporarily stopped. The feed drive comprises a planetary gearing having two inputs, of which the first input can receive a constant rotary motion, and the second input can receive, at the start of the seam formation, a continuous rotary motion which is subtractively superimposed upon the rotary motion at the first input, and, during the ordinary sewing operation, an oscillatory motion whose frequency is equal to the frequency of the needle bar motion.