Asee peer logo

Instrumentation for Highly Accurate Index Measurement of Liquid

Download Paper |


2011 ASEE Annual Conference & Exposition


Vancouver, BC

Publication Date

June 26, 2011

Start Date

June 26, 2011

End Date

June 29, 2011



Conference Session

Effective Projects and Experiments in Instrumentation and Control

Tagged Division


Page Count


Page Numbers

22.892.1 - 22.892.9



Permanent URL

Download Count


Request a correction

Paper Authors

author page

Chao-Chia Cheng National Central University


Lee king-lien Department of Electro-Optic Engineering, National Taipei University of Technology, Taipei, Taiwan 542, R.O.C.

visit author page

Ph.D., Associate professor, Department of Electro-Optic Engineering, National Taipei University of Technology

visit author page

author page

Chih-Hsiung Ku National Dong Hwa University

Download Paper |


  Instrumentation for Highly Accurate Index Measurement of LiquidAbstract:The index of refraction is one important optical property of materials. It also providesinformation to analyze liquids or mixed solutions, such as chemicals, foodstuffs,drinks, and pharmaceuticals. In this work, we introduced a creative indexmeasurement method which aligned one penetrated laser beam to be incidentnormally on the exit surface of a prism shaped cell, and the index of liquid inside canbe deduced by the incident angle on the entrance surface according to Snell’s law.The measurement error was under 5  105 for DI water. With this method, we wouldbe capable to distinguish the index variation within 1 Celsius degree. This methodpresented similar merits as minimum deviation method inherently. However, thesimplicities in measurement process and experimental parameters showed greatpotential for accurate index measurement applications.Most of the design and developing works of this measurement system was performedby undergraduate students from Physics Department and Department of Optics andPhotonics. The hardware integration and the data-acquire automation providedpractical learning opportunities for the topics about optics, electronics, programming,and data analysis. The index measurement results can also provide much insight aboutthe temperature or concentration related index variation of liquid. 

Cheng, C., & king-lien, L., & Ku, C. (2011, June), Instrumentation for Highly Accurate Index Measurement of Liquid Paper presented at 2011 ASEE Annual Conference & Exposition, Vancouver, BC. 10.18260/1-2--18198

ASEE holds the copyright on this document. It may be read by the public free of charge. Authors may archive their work on personal websites or in institutional repositories with the following citation: © 2011 American Society for Engineering Education. Other scholars may excerpt or quote from these materials with the same citation. When excerpting or quoting from Conference Proceedings, authors should, in addition to noting the ASEE copyright, list all the original authors and their institutions and name the host city of the conference. - Last updated April 1, 2015