教你自制一个真4K投影仪，而且真好用！视频来自YouTube。

Building a TRUE 4k home cinema projector (it’s awesome)

{"@context":"http:\/\/schema.org\/","@id":"https:\/\/www.taholab.com\/21581#arve-youtube-yfvtjq9mcwy6574d7badac53909222241","type":"VideoObject","embedURL":"https:\/\/www.youtube-nocookie.com\/embed\/YfvTjQ9MCwY?feature=oembed&iv_load_policy=3&modestbranding=1&rel=0&autohide=1&playsinline=0&autoplay=0"}

关键的两个镜片：