Thirty-seven design engineers with refraction varying from emmetropia to -6.0-diopter myopia and 5.5-diopter hypermetropia and visual acuity 1.0 (with correction) were examined for the spatial-contrast sensitivity (SCS) of the organ of vision before and after working for 4 h with a liquid-crystal monitor under ordinary conditions and with the use of LS-KOM spectacles having a special light-absorbing (spectral) layer. After 4 h of working under ordinary conditions, a significant decrease in SCS for high frequencies and a slight decrease for medium frequencies were observed. When the LS-KOM spectacles were used, the SCS increased at all frequencies at the beginning of work and was retained at the baseline normal level after 4 h of work, being higher than that after working without the light-absorbing spectacles. It was established that long-term work with an LCD monitor interferes with the perception of high spatial frequencies, while the use of the LS-KOM spectacles increases the SCS and allows its normal level to be maintained during 4 h of work.