摘要:
Thermal wake proximate to an optical element of a telescope (100) may be reduced. Signal(s) related to respective temperatures of support struts (118) supporting the optical element may be generated. The respective temperatures (128) of the support struts may be determined based on the signal(s). Individual support struts (118) may be heated based on the respective temperatures of the support struts. Heating a given support strut may cause the given support strut to thermally expand. Individual support struts (118) may be at least partially enclosed with corresponding shrouds (120). Airspaces may be disposed between individual support struts (118) and the corresponding shrouds (120). Heat emitted in the airspaces by the support struts may be ejected away from the optical element to prevent a thermal wake from reaching a volume proximate to the optical element.
摘要:
A scanning tunneling microscopy apparatus includes a specimen mount (45) on which a specimen (50) is located, a probe (33) for scanning the surface of the specimen (50), and a scanning unit (31, 32, 45) for two- or three-dimensionally changing a relative positional relation between the specimen (50) and the probe (33). A temperature control mechanism is located near the probe (33) and/or the specimen (50) to achieve temperature control. It is thus possible to eliminate an adverse effect upon the resolution of a microscope which results from a temperature variation and to make a measurement under any given temperature condition. The temperature control mechanism includes a Peltier element (35) as a source for heating and cooling and a temperature sensor (37).
摘要:
Le dispositif selon l'invention comporte un premier capteur de température (7) monté en contact avec la surface périphérique d'un tronçon de câble (1) en mesure. Ce capteur connecté à une entrée d'un amplificateur d'asservissement (8) dont l'autre entrée est reliée à un capteur de température monté sur une gaine de protection thermique (2) se composant de deux coquilles (3) et (4). Le signal de sortie de l'amplificateur (8) est utilisé pour commander un dispositif de régulation de la température (10) lié à au moins l'une des deux coquilles de la gaine de protection (2). Un dispositif d'asservissement identique peut être utilisé pour les pinces (5) et (6).
摘要:
The present disclosure provides an optical sensing apparatus for measuring a change in a first property. The optical sensing apparatus comprises first and second optical fibre portions and a sensing region for exposing both the first and second optical fibre portions to a change in an applied force. The force is, or is related to, the first property and has a component that is transversal to the optical fibre portions. The apparatus further comprises a holder for holding the first and second optical fibre portions in the sensing region. The first and second optical fibre portions are arranged relative to each other such that the change in the force results in a first change of an optical property of the first optical fibre portion and in a second change of the optical property of the second optical fibre portion and wherein the first change differs from the second change.
摘要:
A device which substantially compensates for the expansion or contraction of a machining apparatus to varying temperatures in and among the components of the machining apparatus links two axes of movement of the machining apparatus by providing a measurement axis (MA) defined by the intersection of a first vertical plane passing through the cutting tip of a cutting tool and a second vertical plane passing through the workface of a workpiece to be machined, and associating one end (32b) of a temperature-insensitive member (32) with this measurement axis, the other end (32a) of the temperature-insensitive member (32) being in the same vertical plane as a reference point which remains stationary with respect to the measurement axis regardless of the thermal growth of the components of the machining apparatus.
摘要:
A support system is disclosed for restraining large masses (1) at very low or cryogenic temperatures. The support system employs a tie bar (68) that is pivotally connected at opposite ends to an anchoring support member (62c) and a sliding support member (62d). The tie bar (68) extends substantially parallel to the longitudinal axis of the cold mass assembly (12), and comprises a rod (102) that lengthens when cooled and a pair of end attachments that contract when cooled. The rod and end attachments are sized so that when the tie bar is cooled to cryogenic temperature, the net change in tie bar length is approximately zero. Longitudinal force directed against the cold mass assembly is distributed by the tie bar between the anchoring support member (62c) and the sliding support member (62d).
摘要:
A displacement generation device includes: a bimorph piezoelectric vibrator (10) for receiving an externally applied drive voltage and for generating a displacement in response to the drive voltage; and a temperature-compensation capacitor element (16) electrically connected in series with the piezoelectric vibrator (10). The capacitor element (16) has a capacitance with a temperature coefficient with the same absolute value but opposite sign to that of the capacitance of the piezoelectric vibrator (10). When the capacitance of the piezoelectric vibrator (10) changes in accordance with a change in the ambient temperature, the capacitor element (16) properly changes the drive voltage supplied to the piezoelectric vibrator (10), thereby compensating for the displacement of the piezoelectric vibrator (10) caused by the change in ambient temperature.
摘要:
Thermal wake proximate to an optical element of a telescope (100) may be reduced. Signal(s) related to respective temperatures of support struts (118) supporting the optical element may be generated. The respective temperatures (128) of the support struts may be determined based on the signal(s). Individual support struts (118) may be heated based on the respective temperatures of the support struts. Heating a given support strut may cause the given support strut to thermally expand. Individual support struts (118) may be at least partially enclosed with corresponding shrouds (120). Airspaces may be disposed between individual support struts (118) and the corresponding shrouds (120). Heat emitted in the airspaces by the support struts may be ejected away from the optical element to prevent a thermal wake from reaching a volume proximate to the optical element.