Improving the accuracy of jarrell-ash microphotometers
Applied Optics
|February 6, 2010
Summary
A modified Jarrell-Ash microphotometer improves spectroscopic plate reading accuracy by 2-5 times. This field-installed upgrade uses affordable components, eliminating plate drive slippage for enhanced precision.
Area of Science:
- Spectroscopy
- Analytical Chemistry
- Instrumental Analysis
Background:
- Spectroscopic plates require precise reading for accurate data analysis.
- Traditional microphotometers can suffer from mechanical limitations like plate drive slippage.
- Existing instruments may lack the desired level of reading accuracy.
Purpose of the Study:
- To describe a cost-effective modification for the Jarrell-Ash model 23-100 recording microphotometer.
- To enhance the plate reading accuracy and reliability of the microphotometer.
- To present a field-installable upgrade using readily available components.
Main Methods:
- Modification of a Jarrell-Ash model 23-100 recording microphotometer.
- Integration of a stepper motor chart recorder driven by plate motion.
- Utilizing inexpensive, off-the-shelf electronic components for the upgrade.
Main Results:
- Achieved a 2-5 fold improvement in plate reading accuracy.
- Successfully eliminated issues related to occasional plate drive slippage.
- The modification was successfully installed and validated in a field setting.
Conclusions:
- The described modification offers a significant enhancement to microphotometer performance.
- This upgrade provides a practical and economical solution for improving spectroscopic data acquisition.
- The enhanced instrument ensures more reliable and accurate readings from spectroscopic plates.
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