What is the Difference Between Filter Photometer and Spectrophotometer?

The main difference between a filter photometer and a spectrophotometer lies in the way they measure light and the range of wavelengths they can analyze. Here are the key differences:

• Filter Photometer:
• Uses glass filters to select the length of light.
• Provides a single value for absorbance.
• Less expensive, simpler to calibrate, and easier to use for inexperienced personnel.
• Stationary parts, lightweight, and suitable for field use.
• Commonly used for measuring parameters at specific wavelengths, such as water (1.94 microns) or oil (1.72 microns).
• Spectrophotometer:
• Uses a monochromator (with prism or grating) to separate and select the various wavelengths of light.
• Provides values for different wavelengths.
• More expensive, complex, and heavier, making it more suitable for bench use.
• Can easily be set to measure the absorbance at different wavelengths and scan the spectrum of the absorbing substance, offering more flexibility than filter photometers.
• Commonly used for measuring parameters with overlapping absorption bands, requiring more complex mathematical modeling.

Both filter photometers and spectrophotometers are useful for measuring absorbance at specific wavelengths, but spectrophotometers offer more flexibility and the ability to analyze a wider range of wavelengths, making them more suitable for complex measurements and research purposes.

Comparative Table: Filter Photometer vs Spectrophotometer

A filter photometer and a spectrophotometer are both analytical instruments used for measuring the intensity of light, but they have different features and applications. Here is a table highlighting the differences between the two:

In summary, filter photometers are simpler, less expensive, and more portable instruments used to measure light intensity at specific wavelengths. Spectrophotometers, on the other hand, are more complex and versatile instruments that measure light intensity across a range of wavelengths. They are used in various applications, including enzyme-catalyzed reactions and clinical diagnosis.