A spectrophotometer measures the intensity of light transmitted or absorbed by chemical substances. It consists of a light source, monochromator to produce specific wavelengths, sample cell, and detector. There are two main types - single beam measures light intensity before and after a sample, while double beam compares light intensities between a reference and sample path. Spectrophotometers are used across various fields like chemistry, biochemistry, materials science, and more to analyze properties of substances, detect chemical components, and study how compounds interact with light.

1. SPECTROPHOTOMETER
PRINCIPLE AND USES
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2. CONTENTS
 DEFINTION
 STRUCTURE
 PRINCIPLE
 WORKING
 CLASSES
 TYPES
 USES
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3. SPECTROPHOTOMETER
 An apparatus for measuring the
intensity of light in a part of the
spectrum.
 Especially as transmitted or
emitted by particular substances.
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4. A spectrophotometer consists of two
instruments, namely
 Spectrometer for producing light of
any selected color (wavelength)
 Photometer for measuring the
intensity of light
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5. There are four essential parts to a spectrophotometer:
1. Light source
2. Monochromatic or filter
3. Sample cell with holder
4. Detector
INSTRUMENTATION
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6. Spectrophotometry
 To measure how much a
chemical substance absorbs light.
With the help of measuring the
intensity of light as a beam of light
passes through sample solution.
The basic principle is that each
compound absorbs or transmits
light over a certain range of
wavelength.
PRINCIPLE OF SPECTROPHOTOMETER
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8. CLASSES OF SPECTROPHOTOMETER
Spectrophotometers are majorly divided into two classes:
1) Single beam
measures the relative of the beam, before and
after a test sample is inserted.
2) Double beam
 Spectrophotometer compares the intensity of light between two
light paths.
 One path contains a reference sample and other contains the
test sample
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10. TYPES
A spectrophotometer can be of different types such
as
 Fluorescent spectrophotometer
 Optical emission spectrophotometer
 UV visible range Spectrophotometer
 UV infrared spectrophotometer
 Atomic absorption spectrophotometer
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11. Types
UV-V SPECTROPHOTOMETERS
Used in the quantitative determination of solutions of
transition metal ions and highly conjugated organic
compounds
UV-V NEAR-INFRARED SPECTROPHOTOMETERS
It is considered as the most efficient way of spectrometry.
This is because, it is the most affordable type of
spectrometry
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12. Types
OPTICAL EMISSION SPECTROPHOTOMETER
Used to analyze various metal bases such as ferrous metals of
Fe, Co, Ni and Ti base and non ferrous metals of Cu, Al, Pb, Mg
and Zn base
ATOMIC ABSORPTION SPECTROPHOTOMETER
It is widely used method for elemental analysis
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13. Types
Fluoresent spectrophotometer
It involves using a beam of light, usually ultraviolet
light, that excites the electrons in molecules of
certain compounds and causes them to emit light;
typically, but not necessarily, visible light.
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14. USES
 Spectrophotometer contributes an essential instrument in various
research and development organizations and industrial or medical
laboratories.
 This instrument are highly reliable, durable and economical and
includes analysis of multiple components, protein testing can be
performed.
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15. Uses
These spectrophotometers are used in several fields such as
• Physics
•Materials
•Chemistry
•Biochemistry
• Measuring the transmittance or reflectance of solutions
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16. Uses
Areas of applications for spectrophotometers include
• Semi conductors
• Printing
• Forensic examination
• To record how medicines absorb and emit light
• Optical manufacturing
• Study of chemical substances
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