Panasonics latest innovation in PIR motion sensors includes the new Dual Zone Lens type, patented “Approach Sensing Technology” Horizontally Wide Detection type and ‘High Sensitivity-High Density-Long Distance type’.
Panasonic PIRs unique design concept goes from the production of the sensing devices to the internal signal processing, thus guaranteeing an optimal detection capability and high reliability.
Our NaPiOn & PaPIRs sensors all have a standard 3 pin footprint, 2 pins for power supply and 1 pin for output signal, the circuit design once approved can use any of the 160+ standard sensor variations depending on applications sensing/trigger requirements. This allows product designers to finalise hardware in reduced timescales and concentrate on the firmware/software offering of their application.
Many projects succeed because Panasonic sensors allow for quick and easy product hardware development enabling engineers to work on the behavioural pattern modelling associated with their application.
The high levels of interest shown in all areas of building automation has been fuelled by the requirement to detect and automate all areas where there is human movement. Although many devices can detect the movement of a person or the occupancy of an area they often suffer from a lack of refinement and accuracy. In many cases they also have not taken full advantage of circuit miniaturisation. This can be seen very clearly in the case of PIR’s (passive devices that use the thermal infrared emitted by the human body for presence detection). Panasonic PIR sensors offer cost effective motion detectors that are mass-produced for use in a wide range of applications. These ubiquitous devices are widely used in lighting, security systems, occupancy/absence detection, door opening applications, heating & ventilation as individual sensing control units or part of a full BMS system. With a worldwide PIR market now exceeding 100 million units per annum it is certainly an area where, with the commitment of the technical investment needed, a major push has been achieved both in the replacement of non-efficient devices and the creation of new ultra low power units.
PIR motion sensors use electromagnetic radiation in the low infrared spectrum in which radiation emitted by human movement is identified using a PIR detector. Objects that are located within the area of sensitivity generate electromagnetic radiation in the low infrared range and project an image through the focus line of the sensor onto the internal heat- sensitive element. The signal processing electronics then convert the images into electrical signals.
If the heat image remains the same, the output signal of the sensor remains unchanged. If the heat image changes, because the object moves within the area of sensitivity, the optical imaging changes accordingly. This movement results in a change of the output signal that in turn can be evaluated by a window comparator that specifies upper and lower thresholds.
However, miniaturisation of PIR devices can prove problematic when compared to the usual miniaturisation of other electronic control devices. Many of these problems arise due to the structure and characteristics of the sensor device since PIR motion detectors use thermal sensors to detect the small temperature increaser present when the sensor element is exposed to radiation. In addition, the required lens array needed to the focus and detection/ elimination of any returning light sources are increasing difficult to manufacture to the necessary tolerance limits the smaller the overall size. Of equal importance is the necessity to product control circuits that take the lowest quiescent currents possible. Obviously on an individual basis the power utilised in a standby mode is very small but if a larger project is considered the cumulative power taken by some hundreds (or even thousands) of devices can be very significant.
Some years ago, Panasonic R&D investigated the developing building automation markets and set into place a design criteria that has seen many miniature PIR products successfully developed and introduced into many now commonplace applications. A good example – the enigmatically named PaPIRs sensor – combines state of the art miniaturisation with practical specifications that allows a whole host of new applications to be realised. Some of these applications are refinements of existing projects but with added benefits in the aesthetic area whilst others are completely new since they rely on the latest families of detection sensors to offer the necessary technical and size criteria to allow a successful product to be manufactured.
The PaPIRs sensor range covers detection distances from 2m through to 17m and beyond with versions to detect slight body movements, focused spot areas, general area movement and new High Sensitivity-High Density-Long Range sensor. This is to cover a wide area of internal building control. Detection of movement in corridors may require a long-distance version whilst occupation of a room may call for a general area type. New applications such as repeated slight movement detection within a sheltered accommodation environment or spot check areas in doorways for counting purposes push the sensor to offer reliable detection within an often difficult environment. Special ultra low power versions allow long life use in remote wireless detection systems with minimal current drain taken from the power source.
The future of Panasonic miniature PaPIRs sensor is secure, but even so, many new versions are continually being developed or improved. For example, the basic PaPIRs can be extended by designing an internal hybrid circuit consisting of sensors to identify light levels, particular colourings, multiple sensitivities and lens arrangements.