光笔

光笔	guāng bǐ	light pen
光	guāng	light; ray (CL:道) / bright; shiny / only; merely / used up; finished / to leave (a part of the body) uncovered
笔	bǐ	writing brush; writing implement (pen, pencil etc) (CL:支,枝) / brushstroke; stroke (in painting or calligraphy) / (bound form) style of writing; literary manner; technique of brushwork / (classifier) stroke of a Chinese character / (classifier) sum of money; financial transaction; piece of business / (literary) to write (with a brush or pen)