Head Mounted Near-eye Display Technology

Helmet display technology is a near-eye display technology. By being installed on a helmet-mounted, the helmet user can get the clear visual images. And also, it can be used in the virtual display. In this paper, we studied a new type of near-eye display technology. Which allows the users observe the outside world situation, and the user can get visual image information in the helmet-mounted display at the same time. When the user observed the different distance objects, visual images can always kept clearly in the eyes.In this thesis, we used a ZEMAX software to re-design a new set of optical systems on the basis of the existing retinal projection display optical system. The number of the lens, structure of the system, lens's thickness, curvature radius and interval of the original optical system are changed, thus this optical system becomes simplify, therefore, optical parts can be easier processed and improved accuracy. The optical system mainly consists of the collimated laser beam expander optical system and the filter projection optical system. This system uses a wavelength of 532 nm laser as a light source, which is expanded by 4 times. We carried out the evaluation of image quality of optical system. The 1.5mrad visual field range within the wave-front aberration is less thanλ/4.The transfer function of spread collimation system is more than 0.9 at the OTF of 60lp/mm. AIRY DIAM size is 4.367 um. The last mirror to the eye distance of the filter projection optical system is 40mm. The OTF is above 0.6 at the OTF of 60lp/mm.In the subject, we designed the mechanical structure of the retinal projection system. The system is monocular structure. The entire optical system is placed in the top of the human eye. In order to move the display flexibly, the mechanical structure is dominated by the vertical adjusting mechanism, pupil distance adjusting mechanism, the rotating mechanism. Pupil distance adjustment mechanism can achieve the 37 mm course and 4 mm fine-tuning. According to the sensitivity of manual fine-tuning, the accuracy of the coarse is 0.5 to 1, fine-tuning from 0.4 to 0.7. The range of vertical adjustment is 48mm, then the vertical adjustment accuracy is 0.5 to 1; The rotating mechanism can achieve three-dimensional rotation, the rotation angle is 11°. In this article. The filter projection optical system of the retinal projection system is to be assembled and debuged. The OTF measurement tested the installed system. The result is 0.5 at the OTF of 60lp/mm.The optical system of this project design meets the design requirements. The structure can meet the requirements of different users. Pupil distance adjusting mechanism allows the monitor to move horizontally. The vertical adjustment mechanism allows the display to move up and down in front of the eyes. The rotating mechanism can be three-dimensional direction of rotation. The evaluation results of the filter projection optical system show that the system can basically display.