Sign up for an Award
Participate with your entry in one of our professional or student awards.Sign up for an award
You are using an outdated browser. Please upgrade your browser to improve your experience.
In the use of ruler, due to the shortage of the ambient light or even, may lead to draw straight line with original want effect have deviation. This ruler design through the light and paper produced between the diffuse back to lighting effect. Both neither can stimulate people's eyes, and can be a very good solve insufficient light this problem; Conform to the man-machine engineering, beautiful modelling is the design of another window.
South China Normal University