Low-cost optical instrumentation for biomedical measurements

Low-cost instruments for measurement in medicine, biotechnology, and environmental monitoring are presented. Recent developments in optoelectronic technology enable practical compact designs. This article presents the available types of light emitters, detectors, and wavelength selection components that are used in low-cost instruments. The main spectroscopic techniques (absorption, reflectance, luminescence intensity, lifetime, and polarization, evanescent wave and surface plasmon resonance) that are used with these instruments are described. Numerous examples of devices for a broad variety of biomedical measurements are presented. (C) 2000 American Institute of Physics. [S0034-6748(00)00112-X].