Patent ID: 7976161

Claim:
A method to assess objectively a refractive characteristic and/or a lag characteristic of one eye of a patient comprising the steps of: a) positioning the patient's head in a reading position where an object to be read is situated between 25 to 50 cm from the eye or from spectacles plane of the patient and where the patient's head is tilted at an angle β, defined as the angle between the axis of the chest of the patient and the patient's head position, where β is between 10° and 40°; b) determining the refractive characteristic and/or the lag characteristic by using a skiascope, the skiascope being arranged to emit a light beam; and wherein the determination of the refractive characteristic is performed when the patient is viewing a scene and where the light beam passes through the scene, where said scene is plane, the plane being tilted at an angle δ, defined as the angle between the scene plane and a horizontal line, and δ is between 30° and 50°.