The invention relates to a projecting device with high light-engine efficiency for projecting image information onto a surface. The projecting device comprises a light source module, a light source synthesizer, a lighter source homogenizer, an illuminating lens set, a reflecting type image generator and an image projecting mirror set. Through an inverse total reflection type telecentric optical framework, the invention definitely can provide a projecting device or module with smaller size or volume and high optical-mechaical efficiency, provide a miniature projecting device or module for realizing conjugate imaging and also provide a miniature projectin device or module with two paths of LED light sources.