An optical see-through glass type display device , comprising: an optical unit ,wherein the optical unit includes a front plate having a front correcting surface , a rear plate having a rear correcting surface , and an intermediate plate arranged between the front plate and the rear plate ; an image projector (130; 210) for projecting a virtual image; and an image sensor (120; 250) for capturing an ambient scene image; wherein the optical unit is configured to guide the ambient scene image light coming through the front correcting surface to the image sensor and to guide the virtual image light so that the virtual image light outgoes through the rear correcting surface ; wherein a first optical compensation element for compensating the deformation of the ambient scene image caused by the front correcting surface is located in a light path from the front plate to the image sensor (120; 250); the image sensor is optically connected to the front plate via a first optical light guide element ; a second optical compensation element for compensating the deformation of the virtual image to be caused by the rear correcting surface is located in a light path from the image projector (130; 210) to the intermediate plate ; the image projector is optically connected to the intermediate plate via a second optical light guide element ; and the device further comprises a processing module (140; 230) configured to analyze the ambient scene image captured by the image sensor (120; 250) to prepare the virtual image to be provided to the image projector (130; 210) according to the analysis result of the ambient scene image. an optical unit ,wherein the optical unit includes a front plate having a front correcting surface , a rear plate having a rear correcting surface , and an intermediate plate arranged between the front plate and the rear plate ; an image projector (130; 210) for projecting a virtual image; and an image sensor (120; 250) for capturing an ambient scene image; wherein the optical unit is configured to guide the ambient scene image light coming through the front correcting surface to the image sensor and to guide the virtual image light so that the virtual image light outgoes through the rear correcting surface ; wherein a first optical compensation element for compensating the deformation of the ambient scene image caused by the front correcting surface is located in a light path from the front plate to the image sensor (120; 250); the image sensor is optically connected to the front plate via a first optical light guide element ; a second optical compensation element for compensating the deformation of the virtual image to be caused by the rear correcting surface is located in a light path from the image projector (130; 210) to the intermediate plate ; the image projector is optically connected to the intermediate plate via a second optical light guide element ; and the device further comprises a processing module (140; 230) configured to analyze the ambient scene image captured by the image sensor (120; 250) to prepare the virtual image to be provided to the image projector (130; 210) according to the analysis result of the ambient scene image. <EOS>