n.偏菱形(斜方形；斜方六面体)

The basic form of this crystal is a rhomb. 此类晶体的基本形状为一菱面体。

Two opposite corners of this rhomb contain three obtuse angles of 101°55'. 菱面体的两个对顶包含着三个101°55'的钝角。

This would be a bit more obvious if we cut the rhomb to have edge of equal axis. 若把斜方体的棱都切成等长，就可以看得更清楚。

Its back is greenish grey while its body is silvery white with a black rhomb shortly behind the pectoral base. 牠的背部灰绿色，躯干大致银白，胸鳍基部后方有一黑色菱形斑纹。

Currently the improved Fresnel rhomb and retangle prism compound rhomb phase retarders are the ideal and utility-type achromatic phase retarders. 结果表明改进型菲涅耳菱体以及直角棱镜组合型消色差相位延迟器，是目前较理想的实用型消色差相位延迟器。