Patent ID: 7671988

Claim:
A nephelometer device for measuring at least one characteristic of particles that are suspended in a fluid, said nephelometer device comprising: a light source unit for emitting light at a substantially single fixed wavelength into a region containing particles; wherein the light source unit is configured to emit light from a plurality of locations in a manner so that the emitted light follows a Lambertian intensity distribution, the Lambertian intensity distribution being desired for the measurement of the at least one characteristic of particles; a detection unit for receiving light scattered by the particles; wherein the light source unit comprises a plurality of spaced apart light emitting diodes; wherein each of the plurality of light emitting diodes are spaced apart along a semicircular arc; wherein the plurality of spaced apart light emitting diodes are disposed in a first array that includes a plurality of light emitting diodes each emitting substantially the same wavelength and constructed and arranged to be disposed in the same plane and evenly spaced from one light emitting diode to an adjacent one thereof; wherein the plurality of light emitting diodes that are disposed in the semicircular arc provide light that is emitted from the respective plurality of locations towards a focal point that is defined by the semicircular arc positioning of the plurality of light emitting diodes; a diffuser located at the focal point defined by the plurality of light emitting diodes for smoothing the emitted light so that the emitted light follows the Lambertian intensity distribution; and a control unit, the control unit for controlling the intensity the light emitted by each of the spaced apart light emitting diodes, according to the disposition of each light emitting diode, such that the emitted light is at the substantially fixed wavelength and follows the Lambertian intensity distribution, the Lambertian intensity distribution being desired for the measurement of the at least one characteristic.