camera lucida
Concise Oxford English Dictionary © 2008 Oxford University Press:
camera lucida /ˌkam(ə)rə ˈluːsɪdə/
▶noun an instrument in which rays of light are reflected by a prism to produce an image on a sheet of paper, from which a drawing can be made.
– origin C18: from L., ‘bright chamber’, on the pattern of camera obscura.
'camera lucida' also found in these Oxford entries:

