Patent ID: 9612516
Date: 2017-04-04
CPC Classifications: G03B,H04N

Claim:
1. A projection type image display apparatus comprising: a projection optical system having a focus lens whose position is movable along an optical axis; a temperature sensor configured to measure a temperature of the projection optical system; a memory configured to store therein correction information related to a correction formula or function, for correcting a position of the focus lens in accordance with the measured temperature; a focus lens control portion configured to perform control for correcting the position of the focus lens to be placed, based on the measured temperature and the correction information, the correction information stored in advance in the memory, before control is performed by the focus lens control portion; an input portion through which a user manually adjusts the position of the focus lens, wherein control for correcting the position of the focus lens is performed prior to a manual adjustment of the focus lens by the user; a determination portion that determines if there is an operation of the input portion by the user; and a correction portion configured to correct and rewrite at least a portion of the correction information related to the correction formula or function in the memory, based on an amount of movement of the focus lens caused by the input portion if the determination portion determines that there is an operation of the input portion after the focus lens control portion starts to perform control for correcting the position of the focus lens, and to store the corrected correction information related to the correction formula or function as rewritten correction information in the memory.