Research On The Key Technologies Of Binocular Head Mounted Display

Augmented reality head mounted display(HMD)can realize the combination of virtual image and the real world,which makes it irreplaceable in military field and become an indispensable part of the modern military aircrafts.Binocular display mode and colorful display have been proved to be the mainstream trends of the current HMD.Binocular mode has much more advantages than the monocular display mode:The binocular display mode conforms to the fact that human use both eyes to observe.Besides,it can widen field of view and easily realize 3D display.Therefore,the study of binocular HMD is of great importance in modern military filed.Two key techniques of binocular head mounted display are studied:matching characteristics of binocular field of view and the construction of military helmet display demonstration system.As for the first key technique,the method of subjective user test has been applied.The influence of the different assembly positions of the two glasses on the binocular overlap effect is discussed according to the extent of binocular rivalry.The optimum assembly positions are determined to eliminate the impact of binocular rivalry.To realize the second key technique,the framework of ARM + FPGA is utilized,which takes the advantages of ARM processor including expert at processing complicated algorithm and convenient to run operation system(OS).Besides,the merits of parallel algorithm acceleration,abundant logical resources and dynamic reconfigurability of FPGA can speedup the system and make it much more flexible.Xilinx'x ZedBoard is based on the Xilinx Zynq-7000 All Programmable SoC,and used as the hardware platform.Embedded Linux OS is transplanted to the ARM processor and the Qt application program of the display information runs on it.The orientation sensor data of the cellphone is used to simulate the direction and the attitude of the aircraft.These data is transmitted by bluetooth and transformed to serial port forms by bluetooth-serial module.The serial port data is sent to the extent uart of ZedBoard's Programmable Logic(PL)part and the uart driver will be called by the Qt application program so that orientation data can be used on the Qt interface.The interface will be exported to the micro-display by the HDMI port and presented to user's eyes through the optical system made of holographic optical waveguide glasses.The whole helmet display system is built and can be demonstrated successfully.