Light Output vs Screen Reflectivity
Before we get started with room lighting issues, first you need to understand how image light reaches your eyes. For TVs, you look directly at the light that the TV emits from the screen. The type of screen surface can affect how well the images are that reach your eyes. For example, the actual screen panel is preferred over an added glass layer in terms of reducing reflections. Although an additional glass overlay can protect the panel from dust and smudges and is more easily cleaned, it does increase susceptibility to light reflections. Specific LED/LCD TVs may feature either just the screen panel or additional glass overlay, but Plasma TVs typically have glass overlays over their screen panels, which are more reflective. Also, LED/LCD TVs output more light than an OLED or Plasma TV, so if you have a brightly lit room, an LED/LCD TV is generally preferred, minus any light reflection issues. However, another TV characteristic that can affect the images you see is whether the TV has a flat or curved screen TV. Curved screen TVs can distort the light that hits the screen in a brightly lit room, resulting in a poor viewing experience. For video projectors, images are seen as a result of indirect light that is reflected off a projection screen. If the screen does a poor job of reflecting light back into the viewing area, the images may be dimmer than you may require. Light hitting the screen from other sources besides the projector can also affect the amount of light from the projected image that reaches your eyes.
Unwanted Light Sources: Windows and Lamps
Windows are obviously a big issue, as sunlight and nighttime exterior light sources can enter the TV or home theater viewing room and reflect off a TV screen, or wash out images on a projection screen. Lamps and other types of room lighting can also cause problems. Nothing is more annoying than seeing a reflection of a lamp on a TV screen. This means that lamp placement in a TV or projector viewing room is critical unless you turn the lamp off.
Controlling Unwanted Light Sources
Blinds and Curtains: If your TV or home theater room has windows, an effective way to control unwanted light entering your room during video projector or TV viewing is with Venetian blinds or curtains. However, dark-colored blinds and curtains work best. Practical Lamp Placement: If you have lamps in your home theater or TV room, place them so that their light does not reflect off the screen. It is best to place the lamps on either side of the TV screen instead of in a room spot that is in front of the screen. However, if you do have lamps in front of the screen, such as next to your seating position, turn them off when viewing your TV or video projector. By the same token, if you have wall/ceiling lights, make sure you also have a dimming system installed so that you can control the amount of light that they shoot into the room or onto your TV screen.
Sometimes Your Room Can Be Too Dark
Although having a too-bright room or a room with annoying ambient light sources can cause TV or video projector viewing problems, having a room that is too dark can also be an issue. For video projectors, the darker the room the better, but for TV viewing a very dark, or completely dark room can be a problem. The reason that a completely dark room is not a problem for video projectors, is that you are viewing images that reflected off of a very large screen – since the light is reflected, it is softer to your eyes. However, with TVs, it is more like looking directly into the light source – which can cause eyestrain, or even headaches, over long viewing periods in a dark room. Just as you don’t want to allow light sources (windows, lamps) to shine into the room and cause unwanted reflections off of the TV screen, you also don’t want the room to be completely dark.
Bias Lighting
One innovative way to control light, especially addressing room darkness, in a TV or home theater viewing room is with bias lighting. Bias lighting is a technique where an ambient light source is actually placed behind the TV and shines the light to the sides and/or above the back of the TV. If done properly, bias lighting creates an ambient light field that does not shine directly at the viewer, creating a counterbalance to the light coming directly off the TV screen. This setup results in a perceived softening of the direct light coming from the TV screen. It reduces the eye strain from viewing the high brightness of the TV screen, and the viewer perceives a more balanced contrast and color from the TV screen.
Types of Bias Lighting
The simplest way to implement bias lighting (provided the TV is not wall mounted) is to get a simple clip lamp(s) and attach it(them) to the back lip of the stand that your TV is placed on. Point the light so that it reflects off the wall to the sides and top of the TV. It is best to use an LED light bulb, as a CFL or Incandescent light might be too bright. Another method (which you can use with both wall and stand-mounted TVs) is to purchase a bias lighting kit that attaches to the back of your TV. These LED accent light kits provide a strip that contains several small LED lights and a controller. The way the system works is that the strip and controller connect to the TV’s USB port (your TV must have a USB port); the strip will turn on and off when you turn your TV on or off. Also, in some cases, the controller allows the user to set the dominant color of the bias light to best match your TV viewing and wall color.
The Bottom Line
To get the best TV and movie viewing experience, consider:
Moving the TV away from windowsMoving lamps away from the TVAdding blinds to block out the lightAdd bias lighting (although this isn’t for reflection, just for comfort on your eyes)
