The subjective sensation of visual space is primarily a function of brightness pattern organization. The eye is involuntarily drawn to bright objects that contrast with the background. This can be effective to direct attention to detail. This assists the occupant in maintaining a sense of direction and be able to participate in an activity with a minimum of visual interference from the environment. The brightness contrast is basic in visual communication. Excessive contrast can disrupt the ability of the eye to perceive fine detail. Visual acuity is also impaired by glare and may affect the ability to orient oneself and the sense of warmth or coolness associated with the visual space. Visual field should be simplified by minimizing irrelevant cues. The designer must be concerned with the effect of light in defining the space, the structural enclosure without introducing irrelevant patterns or visual confusion.