A photomask or equivalent optical component includes a scattering element in the medium of a substrate, which actively modifies (adjusts/filters the intensity, shape, and/or components of) light that propagates through the substrate. The substrate has a front surface and a back surface and is transparent to exposure light of a photolithography process, i.e., light of given wavelength, at least one mask pattern at the front surface of the substrate and the image of which is to be transferred to an electronic device substrate in a photolithographic process using the photomask, a blind pattern at the front surface of the substrate and opaque to the exposure light, and the scattering element. The scattering element, in addition to being formed in the medium of the substrate, is situated below the blind pattern as juxtaposed with the blind pattern in the direction of the thickness of the substrate. Also, a section of the photomask substrate is irradiated with energy which does not melt and/or vaporize the medium of the photomask substrate to form the scattering element. To this end, a femtosecond laser may be used.