角膜曲率计轴位标准器的研制

The Development of Axial Standard Device for Calibration of Ophthalmometers

为解决角膜曲率计的轴位检定,研制出角膜曲率计轴位标准器,由轴位模拟眼、轴位套筒与测量支架组成。轴位模拟眼为方形柱体,前表面为环曲面,后表面为磨砂平面,轴位模拟眼位于轴位套筒的方形通孔内,轴位套筒放置于测量支架的梯形测量槽内,通过装配和机械定位实现0°、45°、90°和135°的轴位测量,其轴位扩展不确定度U=0.5°(k=2)。实验结果表明,该轴位标准器可以满足各类角膜曲率计的轴位检定和校准。同时,还将提升现有角膜曲率计工作基准的测量能力,并为相关计量检定规程的修订和完善提供技术基础。

In order to resolve the axis calibration of ophthalmometers, aixal standard device is developed which consists of axial model eye, axial sleeve and measurement support. Axial model eye is a square cylinder whose front surface is toroidal and back surface is scrub plane, which is located in the square through hole of axial sleeve, and axial sleeve is located on the trapezoid groove of measurement support. By assembly and mechanical positioning,the measurement of four axes of 0°, 45°, 90° and 135° are achieved and axis uncertainty is about 0.5° with coverage factor of 2, which meets the requirement of axis calibration for different kinds of ophthalmometers. Moreover, the developed axial standard device not only expands measurement capabilities of the existing working standard of ophthalmometers, but also provides technical support for revision of related verification regulations.