Patent ID: 7775664

Claim:
An instrument for measuring a refractive power including an astigmatic axis with retinoscopy, comprising: a projector for projecting light into a pupil of an examined eye; a light receiving device for receiving light reflected from the examined eye; a detector for detecting a tilt angle of the light receiving device with respect to a measurement reference; and a notification unit for conveying information related to a result of detection performed by the detector; wherein the notification unit comprises a monitor for displaying change in required orientation of said instrument an operator must make to correct the tilt angle, wherein the projector comprises a convex lens, a target and a visible light source arranged in this order away from an eye being examined, in addition to a motor, and said light receiving device additionally comprising an image capturing unit having a half mirror, convex lenses arranged on the opposite sides of the half mirror and a charge-coupled device, and a dichroic mirror arranged such that light coming from the examined eye is reflected off the dichroic minor, penetrates the half mirror and is guided to an image capturing surface of the charge-coupled device through the convex lenses, and rays of light from the target are illuminated by the visible light source and focused on a retina of the eye being examined after passing through the convex lens of the projector, reflecting off the half mirror, passing through one of the convex lenses of the image capturing unit, then reflecting off the dichroic mirror and entering the eye being examined.