Papers by Author: Yu Lung Lo

Abstract: Chitosan, β-glycerophosphate, and glycerol are all biocompatible materials for biomedical application. This work successfully developed a thermosensitive hydrogel composed of CS, β-GP and glycerol. The CS/β-GP/glycerol hydrogel can be made as a transparent solution at room temperature and becomes an opaque and turbid hydrogel after heating. The transmission of visible light at different temperature can be measured by a visible micro spectrophotometer combined with a precise temperature control of the demountable liquid cell. A tunable transmission of visible light hydrogel was developed. Moreover, the composition of such hydrogel is safely used and it is potential for biomedical applications.

Abstract: This paper presents a new optical configuration for measuring the phase retardation of optical linear birefringent materials. Phase retardation is measured by a heterodyne light source, which is generated by a Zeeman laser. The measurement system has advantages as a simple optical setup, high stability, small size, and portable owing to the configuration and the use of a Zeeman laser. Using the ratio of amplitudes from two measured heterodyne signals, a simple algorithm can obtain the phase retardation directly. Moreover, we can extend dynamic range of the phase retardation measurement to be 0 180 successfully. According to the experimental results, the average absolute error for the phase retardation of λ / 4 -wave plate sample is determined to be only 2.7 %.