摘要:
A system for monitoring the material changes in a structure is disclosed through the use monitoring instruments embedded within the structure. The instruments have at least one sensor with electrodes in contact with the surrounding material and electronics that are contained within the instrument. The sensor signals are converted to digital and transmitted to an external data logger or computer for display of the digitized signals. The connection between the microcontroller and the data logger can be either through hardwire or RF. Power is provided to the electronic sensors through either external or local methods. A power management system can be used to place the electronics into a sleep mode when not in use. The electronics are encapsulated within potting material within an instrument case that is manufactured from a material having a flexural modulus equal to, or greater than, the surrounding material to prevent mechanical failure of the device before failure of the surrounding material. The case has protective trays to protect the electrodes and rounded adjacent connection lengths to prevent the case from developing cracks.
摘要:
Techniques and systems for measuring absolute thickness, the total thickness variation, and electric resistivity of a semiconductor substrate in a nondestructive optical fashion. Optical absorption is used to measure the absolute thickness of a semiconductor substrate with a light source and a photo transceiver. The thickness is determined by comparing the amount of absorption to a calibrated amount. Both the absolute thickness and total thickness variation of the substrate can be measured based on light absorption using an imaging device. The invention can be used to directly image and measure localized features formed on micro machined substrates. The resistivity of a substrate sample can also be measured by using an alternating electrical signal.
摘要:
A fall velocity indicator/viewer having a sampling compartment, a camera system, and an elongated tunnel for interconnecting the camera system to the sampling compartment. The camera system includes a video camera for continuously monitoring snowflakes as they naturally fall through a viewing area in the sampling compartment. The snowflakes are illuminated by a pair of strobe lights directly and in combination with reflected light from a pair of mirrors. In addition, a mirror in the tunnel provides a reflected view from the top of the snowflakes. The video camera is capable of thereby monitoring multiple views of snowflakes in a single video frame and provide sufficient data to analyze the physical characteristics of the snowflakes as well as aid in making velocity determinations and other observations of naturally falling snowflakes.
摘要:
A control arrangement for terminating the film-heating segment of a sequence of operations for a skin packaging machine. A skin packaging machine having a film supply, a film-bearing frame, an oven for heating the film in the frame, a base having a perforated surface with means for drawing a vacuum at the surface, and means for moving the frame from a position adjacent the oven to a position adjacent the perforated surface of the base further includes a control arrangement for terminating the heating of the film in the frame by the oven substantially responsive to the temperature of the film. The control arrangement includes a temperature sensor positioned adjacent the film in the frame when the frame is adjacent the oven. The temperature sensor cooperates with a temperature comparison circuit in the control arrangement to provide a comparison between the sensor temperature and a reference temperature to produce a comparison signal. The control arrangement is responsive to the comparison signal to terminate the heating of the film in the frame by the oven. The temperature sensor is mounted at the end of a conduit through which pressurized air is supplied at a set rate for cooling the temperature sensor when the oven is not heating the film.
摘要:
A microcomputer based industrial machine control arrangement which includes several operator variable controls. The control arrangement is responsive to settings of the operator variable controls to establish parameters, such as time, in the operation of the machine. The control arrangement also receives a number of machine condition indications, such as through limit switches or the like, and produces various switching commands for elements of the machine during its operation. The particular control arrangement illustrated is described in conjunction with a skin packaging machine for the vacuum application of a film over goods to be packaged.
摘要:
A cantilever structure is provided having a cantilever arm with a piezo-active detector embedded on the surface at the fixed end of the cantilever as well as at a sensing point close to the free end along with an integrated amplification circuitry. Deflection of the cantilever arm is initiated by two different methods: (a) by a force at the free end which induces a surface strain at the base of the cantilever and no strain at the free end and (b) by a torque at the free end which induces a maximum strain at the free end but no strain at the base of the cantilever. In the first case a piezo-active signal is produced only in the detector at the base and in the second case only in the detector close to the free end. When both force and torque cause the deflection of the cantilever end, their contributions are separated by comparing the signals produced by both the detectors with that produced by a third ‘reference’ detector which is not part of the cantilever arm but is still situated in close proximity.
摘要:
Techniques and systems for obtaining the thickness map of a partially transparent substrate in a nondestructive optical fashion. The thickness is determined by comparing the amount of absorption by the substrate to a calibrated amount obtained from a substrate standard with a known thickness that is formed of the same material. Digital signal processing operations are performed to reduce noise and to improve resolution of the thickness map.
摘要:
Techniques and systems for measuring absolute thickness, the total thickness variation, and electric resistivity of a semiconductor wafer in a nondestructive optical fashion. Optical absorption is used to measure the absolute thickness of a semiconductor wafer with a light source and a phototransceiver. The thickness is determined by comparing the amount of absorption to a calibrated amount. Coherent light interference is used to measure the total thickness variation of a substrate. Alternatively, both the absolute thickness and total thickness variation of the substrate can be measured based on light absorption using a CCD imaging device. The resistivity of a wafer sample can also be measured by using an alternating electrical signal.
摘要:
An optoelectronic integrated circuit furnishes a monolithic integration of high-speed transistors, lasers and photodetectors for optoelectronic communication applications. The monolithic device integrates an indium phosphorus (InP) / indium gallium arsenide (InGaAs) emitter-down heterojunction bipolar transistor with an InP/InGaAs quantum well laser and modulator, and a metal-semiconductor-metal photodetector.
摘要:
An optoelectronic integrated circuit furnishes a monolithic integration of high-speed transistors, lasers and photodetectors for optoelectronic communication applications. The monolithic device integrates an indium phosphorus (InP)/indium gallium arsenide (InGaAs) emitter-down heterojunction bipolar transistor with an InP/InGaAs quantum well laser and modulator, and a metal-semiconductor-metal photodetector.