Highly Sensitive Magnetic Sensors Have Opportunities in New Applications
Magnetic sensors detect the presence, strength or direction of a magnetic field that is generated from a source (which could be the Earth’s magnetic field, permanent magnet, electric current, etc.). Magnetic sensors often detect other parameters based on changes or disturbances in magnetic fields, such as, for example, rotational speed, position, proximity, heading, etc. Silicon-based magnetic sensor technologies include Hall effect, anisotropic magetoresistive ( AMR), and giant magnetoresistance (GMR). High volume applications for Hall effect or anisotropic magnetoresistive ( AMR) magnetic sensors have included automotive applications (such as camshaft or crankshaft position or rotational speed sensing, ignition timing, wheel speed sensing in connection with anti-lock braking systems, transmission speed sensing, seat belt tension, etc.).
Magnetic sensors (for example, Hall effect sensors) are also used in varied applications, such as keyboards, encoders, electric motor control, current sensing, proximity sensing, etc. In the consumer electronics arena, magnetic sensors (for example, silicon Hall effect sensors) have been widely used in such applications as flip-cover cell phones. Moreover, Hall effect sensors and AMR sensors have, more recently, been finding opportunities for compassing and heading in GPS-equipped cell phones.
There are key needs for magnetic sensors with improved sensitivity, smaller size, lower power consumption, and greater compatibility with electronic systems. Magnetic sensors with such key enhancements have key opportunities to exploit and potentially disrupt new markets/applications, such as, for example, geophysical exploration, medical devices (such as, for instance, hearings aids, pacemakers, cardiac defibrillators), medical diagnostics, and fluid condition monitoring.
In geophysical exploration area, the established magnetometer technologies, although highly sensitive, are very expensive. Sufficiently sensitive, but considerably lower cost magnetic sensors can allow for more cost-effective and comprehensive detection for such applications as mineral detection or geophysical mapping.
There has been significant activity regarding using magnetic sensors and minuscule magnetic microtags or beads for efficient, streamlined detection of, analytes, proteins, viruses, etc., with potential in such applications as, for example, drug screening, bioassay detection, or point-of-care diagnostic systems. There are also opportunities for very sensitive magnetic field sensors in microfludics techniques that use encoded magnetic microtags for more molecular clinical diagnostics drug discovery applications.
Ultrasensitive magnetic field sensors and magnetic nanoparticles have potential to create biosensors that can produce results rapidly for medical detection, diagnostics, and/or treatment of, for example, heart disease or cancer.
There are also opportunities for smaller, low power magnetic sensors to gain wider usage in such medical devices as hearing aids, and for magnetic sensors with a smaller size, high reliability, and ease of manufacture to find wider use in implantable medical devices, such as pacemakers or implanted cardioverter defibrillators.
Moreover, magnetic sensors have potential, going forward, to cultivate applications in such areas as location/tracking of intrabody objects (such as, for example, catheters) or possibly in enabling more convenient glucose monitoring capable of warning of low and high blood sugar.
Magnetic sensors (i.e., Hall effect sensors) also have potential in continuous monitoring of fluid condition and/or metal debris monitoring in fluids.