Method and apparatus for digitizing electromagnetic radiation measurements by shutter speed control

摘要

This invention relates to a method, device and apparatus for digitizing electromagnetic radiation measurements by control of camera shutter speed. The invention uses an Electromagnetic Radiation Sensitive Device (ERSD), such as for example a camera system containing a CMOS- or a CCD-image chip, to perform precise measurements by high-resolution digital control of the shutter speed. A constant output value is obtained from the ERSD such that any non-linearity and range limitation of the ERSD output is circumvented. The measurement methods and system are applied to chemical tests and analytes, which are used for diagnostic purposes. The method can be used to measure reflectance, transmittance, fluorescence and turbidity.