Patent ID: 7154074

Claim:
A telescope main body, comprising: an objective optical system; a focusing system including a focus adjusting member to be manipulated for focusing and a focusing lens which moves along a direction of an optical axis by operation of the focus adjusting member; an imaging device which captures an object image formed through the objective optical system and the focusing lens; a beam splitter which splits an optical path through the focusing lens into a first optical path directed to the imaging device and a second optical path directed to a user's eye; and a correcting system that performs a correcting operation for correcting a position shift between an image forming position of the object image and a receiving surface of the imaging device caused by diopter variation of a user, wherein the correcting system includes: a focus driving system which relatively moves the image forming position of the object image with respect to the receiving surface in the direction of the optical axis; a focus detecting system which detects a status in which the image forming position of the object image coincides with the receiving surface; and a controller which controls the focus driving system, the controller being provided with a learning function of storing correction data of a preceding correcting operation so that the stored correction data of the preceding correcting operation is reflected in a subsequent correction operation.