Abstract:
A motion sensor has at least two tiers of monitored volumes that are offset from each other. Electromagnetic radiation, such as infrared light, is directed from the monitored volumes onto at least two sets of detector elements having separate outputs on a pyroelectric substrate of an infrared detector. As a warm object, such as a human or an animal, moves through the monitored volumes, the warmth from the object causes the voltage on the outputs of the infrared detector to change. The resultant waveforms are compared and if the two waveforms have a phase relationship corresponding to a critical phase angle that is based on the pitch of the monitored volumes and the offset between the tiers of monitored volumes, an animal-immune motion indication is generated.
Abstract:
To provide a thermal electromagnetic wave detection element, a method for producing a thermal electromagnetic wave detection element, a thermal electromagnetic wave detection device, and an electrical apparatus, which are highly reliable and make it possible to prevent damage or deformation in the vicinity of the corner parts of a void, a thermal electromagnetic wave detection element includes: a semiconductor substrate; a support member provided on the semiconductor substrate; a detection unit that is provided on the support member and is able to extract from a pair of electrodes an electrical signal corresponding to a received amount of electromagnetic waves; and a pair of electrically conductive vias that perforate through the semiconductor substrate and are electrically connected to the pair of electrodes, a void that opens on the support member side being provided between the pair of vias of the semiconductor substrate.
Abstract:
A detecting element has an absorbing section where a temperature rises according to an amount of electromagnetic waves which are absorbed and a detecting section where characteristics change according to an amount of heat which is transmitted from the absorbing section. A method for manufacturing the detecting element includes: forming the detecting section on a substrate; forming a protective film which covers the detecting section; forming a hollow space portion in a region which overlaps with the detecting section of the substrate in a planar view after the forming of the protective film; and forming the absorbing section by applying a liquid body, which contains a material constituting the absorbing section, in a region on the protective film on an opposite side from the detection section, which overlaps with the detecting section in a planar view, and solidifying the liquid body after the forming of the hollow space portion.
Abstract:
An infrared detection circuit includes a charge transferring transistor, a gate control circuit and a negative potential generating circuit. The charge transferring transistor is disposed between a read node configured to be connected to one end of an infrared detection element and a tank node to transfer an electric charge from the infrared detection element to the tank node. The gate control circuit is connected to a gate of the charge transferring transistor. The negative potential generating circuit is connected to the tank node to set the tank node to a negative electric potential when the charge transferring transistor transfers the electric charge.
Abstract:
An apparatus and method are provided for sensing infrared radiation. The apparatus includes a sensor element that is positioned in a magnetic field during operation to ensure a λ shaped relationship between specific heat and temperature adjacent the Curie temperature of the ferroelectric material comprising the sensor element. The apparatus is operated by inducing a magnetic field on the ferroelectric material to reduce surface charge on the element during its operation.
Abstract:
The invention is a device for detecting images formed by thermal infrared radiation. It uses a two dimensional array of thermally sensitive elements formed of material whose capacitance changes with temperature. Changes in capacitance of the detector elements are measured and used to form an electronic representation of the thermal infared image. The detector array can be fabricated using inexpensive materials and processes.
Abstract:
Thermal radiation detection apparatus is provided comprising an array of pyroelectric detectors 1,2,3,4 in which compensation is provided for the effect of ambient temperature changes on the detector outputs and also for d.c. offsets which occur in source follower impedance converters 13 necessarily used with each detector. Single element detectors are used, the end pair of elements 3,4 being shielded from radiation and used as reference elements. Each element has a pair of diodes 11,12 connected in parallel in opposite sense to provide a d.c. path across the element. The reference element outputs are averaged 16,17,18 and fed via a high gain negative feedback loop 19 to the common connection 10 of all the elements. Offset voltages and element signals generated by ambient temperature changes are thereby compensated to the extent that the reference offsets and thermal voltages equal those of the active detector elements.
Abstract:
The capacitive bolometer comprises a detection capacitor having a first-order phase transistion ferroelectric material between two electrodes. The detection capacitor operates during a detection step and a subsequent readout step. During the detection step, a preselected electric field is applied to the detection capacitor to maximize its sensitivity to temperature. A second electric field is applied to the capacitor during the readout step in order to increase responsivity of the detection cell. The detection cells according to the invention can be assembled into disclosed detection arrays.
Abstract:
A miniature passive infrared motion detector consists of an optical system, a pyroelectric polymer film and an electronic circuit. The optical system is made of a curved Fresnel lens and an elongated wave guide having a reflective inner surface. The polymer film is also curved with the same radius as the lens and has two interdigitized electrodes on the rear surface and one uniform electrode on the front surface. The front electrode is covered with infrared absorbent material. The electronic circuit contains a differential amplifier and a threshold detector.
Abstract:
A multimodal and highly compact human presence detector that includes, on a same silicon chip made using CMOS technology, a first array of pixels, made sensitive to far-infrared radiation by depositing a pyroelectric layer, converting the received far-infrared radiation into electrical charges, juxtaposed with at least one second array of pixels sensitive to visible light, converting the received visible light into electrical charges, and a circuit for reading the charges generated in each of the arrays by the visible light or the far-infrared radiation, the detector further including, on top of the silicon chip, an optical element for focusing the far-infrared radiation on the first array, and an optical element for focusing the visible light on the second array.