| 摘要 |
A spot retinoscope is used to assess a refractive error of an eye, and has viewing means (11, 12) for viewing the eye under examination, and projection means (6, 9) for directing a beam of light from a light source (5; 82) into said eye thereby to project a spot of light onto the latter. The divergence and convergence of the beam can be altered by focusing means (6, 48) movable from a normal position in which the beam is divergent, or converges to a point (in use) behind the eye under examination, to a cross-checking position, in which the beam is convergent on a point which, in use, is sufficiently far in front of the eye under examination to enable the user to detect movement of the patch of light projected onto the retina of said eye where any refractive error in the eye has not been corrected by a lens placed between the eye and the retinoscope. The retinoscope may also be used (with a further light source) as a streak retinoscope.
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