What is Glare?
To make an object visible, it must be illuminated, and the reflected light enters the human eye, allowing for vision and perception. Increasing the intensity of light falling on an object makes it more visible, especially when it's in a setting with lower levels of brightness. However, if this is taken to an extreme, it can result in an excessively high contrast between the object and its surroundings, leading to what we commonly refer to as glare.
There are two primary types:
1. Direct: This occurs when an individual looks directly at a bright light source, such as a lamp (light bulb) or an LED chip.
2. Reflected: This occurs when light reflects off highly reflective surfaces like computer screens or glossy surfaces.
How Does It Affect Us?
Glare affects everyone and can have various consequences. It can cause temporarily impaired vision, reduce individual safety, and lead to visual and physical discomfort, such as eye strain, headaches, nausea, or momentary blindness. Prolonged exposure to glare can also result in sustained damage to the visual organs and an individual's overall health.
These effects are typically categorized as either discomfort (physical irritation experienced by the observer) or disability (blocked vision experienced by the observer).
How Do We Control Glare?
Effectively managing glare in luminaire design involves integrating shielding, also known as light cutoff, into the design. This helps control the wide dispersion of light emitted by the LED chip and regulates its distribution. Several methods can be employed to achieve this:
1. Reflectors / Lenses: These components are designed to shape individual beams of light, directing them to a specific point. This focused approach reduces the potential for glare.
2. Diffusers: Luminaires equipped with micro-prismatic diffusers offer excellent low-glare light output due to their material structure. These diffusers consist of numerous small prisms dispersing light beams in all directions, effectively concealing the line of sight to the original light source.
3. Recessing: Luminaires with a deep recess, often referred to as a baffle, hide the light source from the observer's line of sight. This design creates a spread of light aimed at providing optimal visual comfort.
