Spectrophotometer

Holmarc's Spectrophotometer (Model No: HOED- TH-01) is ideal for education, research and industrial applications. Unlike other entry level spectrophotometers, it employs the classic Czerny - Turner monochromator design, which ensures low stray light. It uses 1200 lines/mm blazed holographic grating as the dispersion element providing high wavelength resolution. It also employs a sigma delta ADC of 16 bit resolution for photometric measurements. A graphic LCD screen is used to plot an absorbance v/s wavelength graph. The data can then be analyzed for peaks and valleys.

The spectrophotometer can measure the amount of absorbance or lack of absorbance of different colored light for a given molecule. The absorbance spectrum is a graph of a sample's absorbance at different wavelengths.

In a spectrophotometer, the amount of light passing through the sample cell is measured by a photometer. The photometer delivers a voltage signal to a processing unit. The signal changes as the amount of light absorbed by the liquid changes. According to Beer's law, the amount of light absorbed by a medium is proportional to the concentration of the absorbing material or solute present. Thus the concentration of a colored solute in a solution can be determined in the lab by measuring the absorbance of light at a given wavelength.

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