Abstract: The present invention provides a smoke sensor of sound wave type that excels in responsiveness and has a low probability of false detection. The smoke sensor has a sound wave generating unit that provides an ultrasound wave to a monitoring space, a sound wave receiving unit that receives the ultrasound wave from the sound wave generating unit via the monitoring space, and a signal processing unit that detects an abnormality of the monitoring space by using an output of the sound wave receiving unit. The signal processing unit includes a smoke density estimation unit that estimates a smoke density in the monitoring space on the basis of a difference between the output of the sound wave receiving unit and a standard value, and a smoke density determination unit that determines the abnormality of the monitoring space by comparing the smoke density estimated by the smoke density estimation unit with a predetermined threshold.

Abstract: The infrared optical filter of the present invention comprises a substrate formed of an infrared transmitting material and a plurality of filter parts arranged side by side on one surface side of the substrate. Each filter part includes: a first ?/4 multilayer film in which two kinds of thin films having mutually different refractive indices but an identical optical film thickness are alternately stacked; a second ?/4 multilayer film in which the two kinds of thin films are alternately stacked, said second ?/4 multilayer film being formed on the opposite side of the first ?/4 multilayer film from the substrate side, and; and a wavelength selection layer interposed between the first ?/4 multilayer film and the second ?/4 multilayer film, said wavelength selection layer having an optical film thickness different from the optical film thickness of each the thin film according to a desired selection wavelength.

Abstract: A pressure wave generator is provided, which has excellent output stability over time. This pressure wave generator comprises a substrate, a heat generating layer, and a heat insulating layer formed between the substrate and the heat generating layer. A pressure wave is generated in a surrounding medium (air) by a change in temperature of the heat generating layer, which is caused upon energization of the heat generating layer. The heat insulating layer comprises a porous layer and a barrier layer formed between the porous layer and the heat generating layer to prevent diffusion of reactive substances such as oxygen and moisture in the air and impurities into the porous layer. By the formation of the barrier layer, it is possible to prevent a reduction in output of the pressure wave generator caused by a change over time of the porous layer.

Abstract: A fire alarm system, determining existence or nonexistence of a fire by using an ultrasound wave, comprises a sound wave generator and a sound wave detector to detect sound waves propagated through two propagation paths having different lengths each other. The system comprises a calculation means for calculating a pressure ratio between a first sound pressure, which is a sound pressure of a sound wave propagated through a first propagation path, and a second sound pressure, which is a sound pressure of a sound wave propagated through a second propagation path, and a smoke density estimator. The smoke density estimator calculates a change ratio between the pressure ratio calculated by the calculation means and a predetermined standard pressure ratio, and determines a smoke density from the change ratio based on a predetermined relational expression describing the relation between the change ratio and the smoke density, and determines existence of a fire when the smoke density exceeds a predetermined threshold.

Abstract: An infrared sensor unit has a thermal infrared sensor and an associated semiconductor device commonly developed on a semiconductor substrate. A dielectric top layer covers the substrate to conceal the semiconductor device formed in the top surface of the substrate. The thermal infrared sensor carried on a sensor mount which is supported above the semiconductor device by means of a thermal insulation support. The sensor mount and the support are made of a porous material which is superimposed on top of the dielectric top layer.

Abstract: In an anodic oxidation apparatus and an anodic oxidation method and a panel for a display device manufactured by them, a large target substrate is treated by a smaller component.

Abstract: The present invention provides a smoke sensor of sound wave type that excels in responsiveness and has a low probability of false detection. The smoke sensor has a sound wave generating unit that provides an ultrasound wave to a monitoring space, a sound wave receiving unit that receives the ultrasound wave from the sound wave generating unit via the monitoring space, and a signal processing unit that detects an abnormality of the monitoring space by using an output of the sound wave receiving unit. The signal processing unit includes a smoke density estimation unit that estimates a smoke density in the monitoring space on the basis of a difference between the output of the sound wave receiving unit and a standard value, and a smoke density determination unit that determines the abnormality of the monitoring space by comparing the smoke density estimated by the smoke density estimation unit with a predetermined threshold.

Abstract: A pressure wave generator is provided, which has excellent output stability over time. This pressure wave generator comprises a substrate, a heat generating layer, and a heat insulating layer formed between the substrate and the heat generating layer. A pressure wave is generated in a surrounding medium (air) by a change in temperature of the heat generating layer, which is caused upon energization of the heat generating layer. The heat insulating layer comprises a porous layer and a barrier layer formed between the porous layer and the heat generating layer to prevent diffusion of reactive substances such as oxygen and moisture in the air and impurities into the porous layer. By the formation of the barrier layer, it is possible to prevent a reduction in output of the pressure wave generator caused by a change over time of the porous layer.

Abstract: An infrared sensor unit has a thermal infrared sensor and an associated semiconductor device commonly developed on a semiconductor substrate. A dielectric top layer covers the substrate to conceal the semiconductor device formed in the top surface of the substrate. The thermal infrared sensor carried on a sensor mount which is supported above the semiconductor device by means of a thermal insulation support. The sensor mount and the support are made of a porous material which is superimposed on top of the dielectric top layer.

Abstract: Even when compression stress is generated because a volume of a thermal insulation layer 2 is expanded due to oxidized by oxygen in the air, occurrence of cracks and fractures of the thermal insulation layer and a heating conductor 3 caused by the cracks are prevented by dispersing the compression stress. A pressure wave generator comprises a substrate 1, the thermal insulation layer 2 of porous material which is formed on a surface of the substrate 1 in thickness direction, and the heating conductor 3 of thin film formed on the thermal insulation layer 2, and generates pressure waves by heat exchange between the heating conductor 3 and a medium.

Abstract: In an acoustic wave sensor for detecting a distance to an object and an orientation where the object is located with using acoustic waves, an acoustic wave generating device generating an acoustic wave by applying thermal impact to the air with no mechanical vibration is used as a wave transmitting device, and an electric capacitance microphone converting variation of pressure due to acoustic wave to variation of an electric signal is used as each wave receiving device. Therefore, dead zone caused by reverberation component included in the acoustic wave transmitted from the wave transmitting device and dead zone caused by reverberation component included in wave receiving signals outputted from the wave receiving devices can be shortened and angular sensitivity of the acoustic wave sensor can be increased, in comparison with a conventional acoustic wave sensor using piezoelectric devices as the wave transmitting device and the wave receiving devices.

Abstract: Even when compression stress is generated because a volume of a thermal insulation layer 2 is expanded due to oxidized by oxygen in the air, occurrence of cracks and fractures of the thermal insulation layer and a heating conductor 3 caused by the cracks are prevented by dispersing the compression stress. A pressure wave generator comprises a substrate 1, the thermal insulation layer 2 of porous material which is formed on a surface of the substrate 1 in thickness direction, and the heating conductor 3 of thin film formed on the thermal insulation layer 2, and generates pressure waves by heat exchange between the heating conductor 3 and a medium.

Abstract: In an anodic oxidation apparatus and an anodic oxidation method and a panel for a display device manufactured by them, a large target substrate is treated by a smaller component.

Abstract: In a field emission-type electron source (10), a strong field drift layer (6) and a surface electrode (7) consisting of a gold thin film are provided on an n-type silicon substrate (1). An ohmic electrode (2) is provided on the back surface of the n-type silicon substrate (1). A direct current voltage is applied so that the surface electrode (7) becomes positive in potential relevant to the ohmic electrode (2). In this manner, electrons injected from the ohmic electrode (2) into the strong field drift layer (6) via the n-type silicon substrate (6) drift in the strong field drift layer (6), and is emitted to the outside via the surface electrode (7).

Abstract: Disclosed is a method for the electrochemical oxidation of a semiconductor layer. In an electrochemical oxidation treatment for the production process of an electron source 10 (field-emission type electron source) as one of electronic devices, a control section 37 determines a voltage increment due to the resistance of an electrolytic solution B in advance, based on a detected voltage from a resistance detect section 35. Then, the control section 37 controls a current source to supply a constant current so as to initiate an oxidation treatment for a semiconductor layer formed on an object 30. The control section 37 corrects a detected voltage from a voltage detect section 36 by subtracting the voltage increment therefrom. When the corrected voltage reaches a given upper voltage value, the control section 37 is operable to discontinue the output of the current source 32 and terminate the oxidation treatment.

Abstract: An array of field emission electron sources and a method of preparing the array which discharges electrons from desired regions of a surface electrode of field emission electron sources. The field emission electron source 10 comprises an electrically conductive substrate of p-type silicon substrate 1; n-type regions 8 of stripes of diffusion layers on one of principal surfaces of the p-type silicon substrate, strong electric field drift layers 6 formed on the n-type regions 8 which is made of oxidized porous poly-silicon for drifting electrons injected from the n-type region 8; poly-silicon layers 3 between the strong field drift layers 6; surface electrodes 7 of the stripes of thin conductive film formed in a manner to cross over the stripes of the strong field drift layer 6 and the poly-silicon layers 3.

Abstract: Disclosed is a method for the electrochemical oxidation of a semiconductor layer. In an electrochemical oxidation treatment for the production process of an electron source 10 (field-emission type electron source) as one of electronic devices, a control section 37 determines a voltage increment due to the resistance of an electrolytic solution B in advance, based on a detected voltage from a resistance detect section 35. Then, the control section 37 controls a current source to supply a constant current so as to initiate an oxidation treatment for a semiconductor layer formed on an object 30. The control section 37 corrects a detected voltage from a voltage detect section 36 by subtracting the voltage increment therefrom. When the corrected voltage reaches a given upper voltage value, the control section 37 is operable to discontinue the output of the current source 32 and terminate the oxidation treatment.

Abstract: An electron source (10) has an electron source element (10a) including a lower electrode (12), a drift layer (6) and a surface electrode (7). The drift layer (6) is interposed between the lower electrode (12) and the surface electrode (7). When a certain voltage is applied between the surface electrode (7) and the lower electrode (12) such that the surface electrode (7) has a higher potential than that of the lower electrode (12), a resultingly induced electric field allows electrons to pass through the drift layer (6) and then the electrons are emitted through the surface electrode (7). When a forward-bias voltage is applied between the surface electrode (7) and the lower electrode (12), a reverse-bias voltage is applied after the forward-bias voltage has been applied to release out of the drift layer (6) an electron captured by a trap (9) in the drift layer (6).

Abstract: A field emission-type electron source 10 includes an insulative substrate 11 in the form of a glass substrate having an electroconductive layer 8 formed thereon. A strong electrical field drift layer 6 in the form of an oxidized porous polycrystalline silicon layer is formed over the electroconductive layer 8. This electroconductive layer 8 includes a lower electroconductive film 8a, made of copper and formed on the insulative substrate 11, and an upper electroconductive film 8b made of aluminum and formed over the electroconductive film 8a. The strong electrical field drift layer 6 is formed by forming a polycrystalline silicon layer on the electroconductive layer 8, rendering the polycrystalline silicon layer to be porous and finally oxidizing it. The upper electroconductive film 8b has a property that reacts easily with silicon and, therefore, formation of an amorphous layer which would occur during formation of the polycrystalline silicon layer can be suppressed.

Abstract: An electron source 10 has an n-type silicon substrate 1, a drift layer 6 formed on one surface of the substrate 1, and a surface electrode 7 formed on the drift layer 6. A voltage is applied so that the surface electrode 7 becomes positive in polarity relevant to the substrate 1, whereby electrons injected from the substrate 1 into the drift layer 6 drift within the drift layer 6, and are emitted through the surface electrode 7. In a process for manufacturing this electron source 10, when the drift layer 6 is formed, a porous semiconductor layer containing a semiconductor nanocrystal is formed in accordance with anodic oxidation. Then, an insulating film is formed on the surface of each semiconductor nanocrystal. Anodic oxidation is carried out while emitting light that essentially contains a wavelength in a visible light region relevant to the semiconductor layer.