Optimal achromatic wave retarders using two birefringent wave plates

Abstract

Two plates of different birefringence material can be combined to obtain an achromatic wave retarder. In this work, we achieve a correction for the overall retardation of the system that extends the relation to any azimuth. Current techniques for the design of achromatic wave retarders do not present a parameter that characterizes its achromatism on a range of wavelengths. Thus, an achromatic degree has been introduced, in order to determine the optimal achromatic design composed with retarder plates for a spectrum of incident light. In particular, we have optimized a quarter retarder using two wave plates for the visible spectrum. Our technique has been compared to previous results, showing significant improvement.

Optimal achromatic wave retarders using two birefringent wave plates: reply

“…(11) in Ref. [2] is correct and the achromatic wave retarder obtained is valid. It is noteworthy that the condition ϕ 0 or ϕ π∕2 must be imposed, instead of derived, as we show.…”

“…This article is a reply to comment of Zhang [1] about our previous article [2]. First of all, we would like to express our gratitude to the author for his interest in our work.…”

“…First of all, we would like to express our gratitude to the author for his interest in our work. In our paper [2], the main objective was the design of achromatic retarders using two wave plates with different birefringence. The optimization of this achromatic retarder was performed with a merit function that measured the distance between the overall retardation and the retardation target, in our case π∕2 rad.…”

“…(3) and (4) (4) is wrong. For that reason, we tried to obtain the overall retardation via diagonalization of the matrix product [2]. However, the diagonalization is valid only when ϕ 0 or ϕ π∕2 rad, since the matrix product is diagonal.…”

Theoretical Analysis of Two-in-one Composite 1/4 Wave-plate

“…When the angle between the fast of axis is a specific value, the wave-plate system composed by two wave-plates of arbitrary retardation, emergent light of the system can be elliptically polarized light though the incident light is linearly polarized light, which can replace the 1/4 wave-plate [7][8][9][10][11]. That literatures [12][13][14] have given the formula to us when a wave plate merge with another, but it hasn't explained how to use these formula. In fact, it cannot be calculated because of the limitation of value range of tangent function and cotangent function when applying 1/4 wave-plate merge with 1/2 wave-plate.…”