What Is A Spectrophotometer Used For?

In chemical and biological science, the spectrophotometer is a very common tool and it has a wide variety of uses. But what does a spectrophotometer actually do?

Spectrophotometers are instruments used to send electromagnetic radiation into a given target to measure the resulting interaction of energy and the target. The UV spectrophotometer is used to measure the absorption spectrum in the 360-600 nanometer wavelength of a spectrum. The absorption versus the spectrum data is then converted into information for digital display.

How It Works

what does a spectrophotometer measureThe first step towards using a simple spectrophotometer is to set the needle to the left zero by using the left knob. The needle might drift and should be adjusted during this time. The process is known as zeroing the light output. This process is a means of maintaining standard operating conditions on a daily basis.

The light rail is then tracked from the lamp to the right towards the reflecting diffraction grating, which resolves incident light into its spectrum. The grating moves as the wavelength cam is moved which shifts the direction of the reflected spectrum and separates the different intensities of light at different wavelengths.

The lights then interact with the sample, which allows the light beam to interact with the phototube displaying the intensity on the meter. The detector measures the absorbance and transmittance of the sample at this point. The transmittance is the amount of energy passing through a sample while absorbance is the light that is absorbed by the sample. The detector senses the light through the sample and converts it into information.

Uses Of A Spectrophotometer

For the measurement of the transmittance and reflectance of solutions , polished glass, transparent or opaque solids and gases.

To measure diffusivity of light ranges using different controls and calibrations dedicated to various tasks.
Some are used in industries for the study of chemicals.
To determine which substances are present in a target at a particular point in time.

  • Respiratory gas analyses in health facilities depend on this technology.
  • Space exploration
  • The characterization of proteins
  • Applied in the study of spectral emission lines of galaxies
  • In monitoring the content of dissolved oxygen in marine and fresh water ecosystems

Spectrophotometers are extremely valuable as they see a color drift long before the human eye can. Our human vision is dependent on alot of factors that are changeable, e.g. the time of the day, age, genetics and many other parameters . On the other hand, a spectrophotometer is consistent and will give you accurate color data time after time if they are well maintained . For print rooms, spectrophotometers ensure that press operators match colors expertly to meet customers’ expectations.

Sources

http://scienceinthetriangle.org/spectrophotometers/