Abstract: An optical element is configured to transmit a light flux emitted from a light source having a single light source wavelength, and is formed from a material in which resin and glass fillers are mixed. A difference between respective refractive index change rates (dn/dT) of the resin and the glass fillers relative to a temperature change at least in a vicinity of the light source wavelength becomes 10.5×105 or less.

Abstract: An image-taking apparatus permits annotation information to be added to a region within an image not only with an image that has already been recorded but also with an image that is going to be captured, and thus with higher efficiency. In one screen, either an image that is going to be captured or an image recorded on a recording medium is specified as a parent image to which to add annotation information. When the former is specified, a parent image is newly captured; when the latter is specified, in another screen, which of already recorded images to select is specified, and the specified image is used as a parent image. Within the parent image, a region to which to add annotation information is specified, and then, as the annotation information, an image is captured or a sound is recorded.