基于4k分辨率小型投影机的鱼眼镜头设计

基于一款4k分辨率小型投影机，设计了一种低成本、易加工的小口径高分辨率鱼眼投影镜头。通过合理选型、分配光焦度、设置光栏位置、调整镜片形状、材料优选及匹配等途径，在镜片数量较少的情况下对像差进行了充分的校正。该镜头仅由9片透镜组成，视场角为175°，F#为2.2，后工作距达到39.8 mm，在奈奎斯特频率131 lp/mm处，1.0视场MTF值达到0.3，其余视场MTF值均达到0.43以上，满足了该机型的使用需求。对镜头的各项公差进行了蒙特卡罗分析，结果表明，公差均在常规可加工的范围内，适合于批量加工和装配。

Fisheye lens design based on small-sized projector with 4k resolution

Based on a small-sized projector with 4k resolution, an easy processing fisheye lens with low cost, small diameter and high resolution was designed. Through rational selection of structure, focal power distribution, aperture position setting, lens shape adjustment, materials optimization and match, the image aberration was fully corrected. The lens only consist of nine glasses, with the field angle of 175°, F# of 2.2, back focal length of 39.8 mm. At the Nyquist frequency of 131 lp/mm, the MTF of 1.0 field is 0.3, the MTF of other fields are all above 0.43. All the technique parameters meet the requirements of using the projector. The Monte Carlo analysis results show that all the tolerance is in the normal range that is feasible to process, hence the lens is fit for batch production and assembly.