Patent ID: 8573788

Claim:
An image projecting apparatus comprising: an image display element; and an optical system that projects an image displayed on the image display element onto a screen, wherein the optical system comprises: an optical element that shifts in a direction having a component in a direction perpendicular to an optical axis of the optical system; and an adjusting mechanism that shifts the optical element in a direction having a component in a direction perpendicular to the optical axis, wherein the following conditions are satisfied: νdch <35, and 0.5 (mm 2 )<| P×fdch|< 1.3(mm 2 ), where vdch is a combined Abbe number of materials of the optical element with respect to a d-line, fdch is a combined focal length of the optical element with respect to the d-line, and P is a pixel pitch of the image display element, and wherein the optical element is a single lens, or the optical element includes a positive lens and a negative lens, wherein in a case where the optical element includes the positive lens and the negative lens, vdch is a combined Abbe number of materials of the optical element with respect to a d-line, which is defined by νdch=1/[fdch×{1/(fp×νp)+1/(fn×νn)}], and fdch is a combined focal length of the optical element with respect to the d-line, which is defined by 1/fdch=1/fp+1/fn, where fp is a focal length of the positive lens included in the optical element, νp is an Abbe number of the material of the positive lens included in the optical element, fn is a focal length of the negative lens included in the optical element, and νn is an Abbe number of the material of the negative lens included in the optical element, and wherein in a case where the optical element is a single lens, vdch is a Abbe number of the material of the single lens with respect to the d-line, and fdch is a focal length of the single lens with respect to the d-line.