The development of a fixation system is discussed in this article based on the fixation system of OCT. The key technique can be used in other ophthalmic instruments. Optical coherence tomography (OCT) is a novel tomography imaging technique. It provides cross-sectional tomography image of the microstructure of biological tissue with high depth and transversal resolution. Featuring in the fast, noninvasive and high resolution imaging, OCT is widely applied in the field of ophthalmology. Due to its high resolution, the scanning range of OCT is rather limited. Thus in a commercial ophthalmic OCT, a fixation system based on LED dot matrix or LCD display is always introduced in. Along with the movement of visual target, different place of retina will be scanned and image of the whole retina is obtained.
This article puts forward with a new scheme of fixation system based on organic light-emitting diode (OLED) Display. From the user’s operation in the upper computer to the output of the ultimate screen display, the hardware design scheme and software flow charts of both PC and 8051 are studied in detail. Hardware design is based on the OLED Reference Design Kit of OSRAM Corp., including DC/DC converter, 8051 control module, OLED driver and RS-232 communication interface. Program of PC is developed in Delphi platform, and should take the user’s need into account. User’s operation is performed by the program in 8051 according to control information from PC. Data transfer and real-time control from upper computer to lower computer is realized by RS-232 standard.
