摘要:
A driving device includes an optical pickup unit that irradiates a disc having a plurality of recording surfaces with a laser beam used for recording or reproducing information, and a generating unit that generates a focus control signal used for controlling a focus state of the laser beam emitted from the optical pickup unit on the basis of a focus error signal. The generating unit includes level detector that detects a level of the focus error signal, an offset generator that generates an offset signal used for performing focus jumping from one of the plurality of recording surfaces to another one of the plurality of recording surfaces in accordance with the focus error signal, and a switcher that switches a polarity of the focus control signal by comparing the level of the focus error signal of the level detector with a threshold value.
摘要:
A glass spacer having no swell at the end portions and no constriction at the middle portion and designed grooves is manufactured by a heating and drawing method. The heat flux output of a line heater for heating a glass base material in a wide area opposed to the glass base material is 95 to 105% of the heat flux output of the center portion in the longitudinal direction of the heater, and the glass base material is heated and drawn with the line heater at a viscosity of 107.0 P or more and less than 108.0 P.
摘要:
A gas sensor (10) including a measurement chamber (28) into which a gas GS is flown and a detection element main body (40) facing the measurement chamber (28). The detection element main body (40) includes an element case 42, and a protective film (48) is adhered to a bottom surface thereof. An acoustic matching plate (50) and a piezoelectric element (51) of a substantially columnar shape and a tube body (52) provided in a position surrounding the acoustic matching plate 50 and the piezoelectric element 51 are housed in the element case (42). A filler is then introduced into the element case (42), whereby the acoustic matching plate (50), the piezoelectric element (51), and the tube body (52) are sealed by a filled layer (99).
摘要:
An ultrasonic-wave propagation time measuring method which enables determination of accurate propagation time, a gas-pressure measuring method, a gas-flow-rate measuring method, and a gas sensor. A reception wave which has been transmitted and received by an ultrasonic element 5 is shaped and integrated by an integration circuit 67 to obtain an integral value. A peak value of the integral value is held by a peak-hold circuit 39. As to detection of gas concentration, a resistance-voltage-division circuit 41 sets a reference value on the basis of the peak value, and a point in time when the integral value of the reception wave is judged by a comparator 43 to have reached the reference value is regarded as an arrival time. Subsequently, a gas concentration is detected on the basis of a period between the emission time and the arrival time. As to detection of gas pressure and flow rate, the gas pressure is detected on the basis of the peak value, and further, the gas flow rate is calculated on the basis of the gas pressure.
摘要:
When a sensor has deteriorated, the propagation time T1′ of a first reflection wave becomes greater than the propagation time T1 of a first reflection wave as measured in a new sensor. If measurement of the concentration of a specific gas is based on the propagation time T1 of the first reflection wave as measured in the new sensor, gas concentration cannot be determined accurately. By contrast, a reflection wave other than the first reflection wave (for example, a second reflection wave) is merely reflected off the surface of the ultrasonic element and is not affected by the internal structure of the ultrasonic element. Therefore, even when the sensor is deteriorated, the propagation time T2, T2′ of the second reflection wave exhibits less variation and is less susceptible to deterioration of the sensor. Therefore, the concentration of a specific gas is determined on the basis of the propagation time of the second reflection wave, which is less susceptible to deterioration of the sensor, instead of the propagation time of the first reflection wave, which is more susceptible to deterioration of the sensor. Thus, gas concentration can be measured accurately.
摘要:
A disc playback apparatus for playing back a disc on which data have been recorded under a CLV control is provided with a CLV control section for performing a CLV control, a speed comparator and a reference clock generator for performing a CAV control, a changeover switch for switching between the CLV control and the CAV control, and a CPU for setting a switching point of the changeover switch and controlling the switching of the changeover switch. According to another aspect of the invention, switching is made between a playback with a CLV servo control and a playback with a CAV servo control in accordance with the reproduction scanning position in the disc radial direction. In particular, a difference between disc rotation speeds at the disc innermost and outermost tracks is made smaller than that in a case where a playback is performed at a specific linear velocity over the disc entire area. According to a further aspect of the invention, regions are set by dividing the disc entire area in the disc radial direction. A judgment is made of a region to which a current reproduction scanning position belongs, and control is made so as to switch the playback linear velocity in accordance with the region thus determined. In particular, a difference between disc rotation speeds at the disc innermost and outermost tracks is made smaller than that in a case where the linear velocity is not changed over the disc entire area.
摘要:
A recording and/or reproducing apparatus in which a recording medium contained in a holder is rotated and driven and a signal is read from or written to the recording medium. In the chassis employed as a base of the recording and/or reproducing apparatus, or in the holder for containing a recording medium, a strengthening rib having a stepped section is formed.
摘要:
A non-aqueous electrolyte secondary battery has a negative electrode, a positive electrode and a non-aqueous electrolyte with lithium ion conductivity. A composite oxide produced from a metal or a metalloid and lithium represented by composition formula Li.sub.x MO (where M represents metals or metalloids other than alkali metals, and x satisifies 0.ltoreq.x) is used as an active material of one or both of the negative electrode and the positive electrode. The battery exhibits a large charging/discharging capacity and a high energy density together with smaller polarization (internal resistance) on charging and discharging which facilitates a large current charging and discharging with a long cycle life and reduces deterioration due to excess charging and excess discharging.
摘要:
Provided is a medical treatment device capable of eliminating inconvenience of manipulation in actual clinical use, and ensuring a visual field by introducing a curve in the vicinity of an electrode portion of an outer cylindrical tube. The medical treatment device has the following structure: an electrode portion including a first electrode and a second electrode arranged opposed to the first electrode, the electrode portion having a grasping function, a coagulating function, and a cutting function; an operation portion for executing drive of the respective functions of the first electrode and the second electrode; a shaft portion for connecting the electrode portion and the operation portion; a connector portion connectable to a microwave power source; and a conductive rod, which is provided inside the shaft portion, for transmitting a microwave to the electrode portion, the medical treatment device utilizing the microwave being configured to: hold body tissue between the first electrode and the second electrode; coagulate the body tissue by supplying the microwave to the first electrode and the second electrode; and cut the body tissue through a mutual action of the first electrode and the second electrode, in which the shaft portion and the electrode portion are connected to each other with a bent holder.
摘要:
Since dispersion of height dimension is reduced in a spacer, it is possible to increase a yield in manufacturing processes and reduce a lord for inspecting products. There is provided a method of manufacturing a plate glass member to be used in an electronic device, the manufacturing method comprising: introducing a glass base material analogous to the glass member into a furnace body of which the temperature has been held equal to or higher than a softening temperature of the glass base material; heat-drawing the glass base material within the furnace body; and extracting the heat-drawn glass base material outside the furnace body, wherein the glass base material is introduced into the furnace body as a gap between the glass base material and an inner wall of the furnace body is shielded at a slot of the furnace body for the glass base material.