Get Adobe Flash player


Friendly Photons: Optical Sensors in Life Science and Medicine

Biology is increasingly a science that relies upon new developments in sensor engineering to provide detailed information about cell function, to perform disease diagnosis, to quantify gene expression, and to image tissue. Of the many transduction methods available for applications including point-of-care diagnostics, personalized medicine, and medical imaging, approaches based upon optics have had a tremendous impact due to a combination of non-invasiveness, robustness, miniaturization, and low cost. (...more details)


Science with Mars Rover Curiosity

he Mars Science Laboratory (MSL) rover, Curiosity, touched down on the surface of Mars on August 5, 2012. It was built to conduct an investigation of modern and ancient habitable environments. The MSL science payload was specifically assembled to assess habitability and includes a gas chromatograph-mass spectrometer and gas analyzer that will search for organic carbon in rocks, regolith fines, and the atmosphere (SAM); an x-ray diffractometer that will determine mineralogical diversity (CheMin); focusable cameras that can image landscapes and rock/regolith textures in natural color (Mastcam, MAHLI); an alpha-particle x-ray spectrometer for in situ determination of rock and soil chemistry (APXS); a laser-induced breakdown spectrometer to remotely sense the chemical composition of rocks and minerals (ChemCam); an active neutron spectrometer designed to search for water in rocks/regolith (DAN); a weather station to measure modern-day environmental variables (REMS); and a sensor designed for continuous monitoring of background solar and cosmic radiation (RAD). This broad and diverse payload, coupled with a rich field site at Gale Crater, already has established the importance of water in shaping the geology and geochemistry around the landing area, addressed long-standing questions regarding Mars' atmospheric composition and evolution, and made serendipitous discoveries not anticipated from orbital data studied prior to landing. (...more details)


Sensors for Non-invasive Diagnostics

Health and physical condition of the human body can be ascertained by making suitable measurements on the physical, electrical, chemical and acoustic signals emanating from it. Any disease or injury causes one or more of these signals to differ from their expected normal form. Quite often information reflecting the functioning or malfunctioning of the underlying biological system is entwined in a complex manner in these signals and hence such information has to be extracted. Conventionally, many of these signals were ascertained in an invasive manner. For example, to obtain the constituents of blood, blood is extracted from a patient and details obtained through a chemical assay. Present trend is to obtain as much information as possible, through noninvasive means. This paper reviews the state of the art in noninvasive measurement of biological parameters that are clinically relevant through the use of appropriate optical sensors. Emphasis is given on the research outcomes of the group to which the author is associated with. (...more details)