I’ve always liked a small task light to the side of display monitors to provide a balance of the brightness of the monitors (usually around 24Footlamberts) with surrounding horizontal work surfaces. For example, in my work area, measured at the viewer position of 18″ from the monitor, I get around 12 Footlamberts brightness at eye height. So, what I look for from a task light is to provide about that amount at the eye from the horizontal surface to my right, about 30″ away. between the reflectivity of the surface, cosine effect of the viewing angle, and distance, I find that anywhere from 90 to 100Fc measured horizontally under the light, works fairly well. The next issue is to eliminate glare from the sources, which is a simple matter of geometry. First, I’ve found a head height of around 14″ to 16″ from the work surface works well. I then like to recess the light source a little into the head itself, to provide a little more cutoff and assure that their is no glare in the monitors, or other vertical surfaces around.

Based on all of this, I made this latest design.  This is a combination of architectural simplicity as well as functionality. With the head at 16″ from the task surface, a dark gray vertical stem (no brightness or glare), recessed LEDs, and the very simple LynkLabs SnapBrite 12VAC LED modules, this simple little task light delivers the target illuminance and takes up very little space on the desk. A simple on-off switch gets the job done, while consumption of just 10.9 watts total while delivering 93Fc on the work surface is exactly what I was looking for. The heat sinks are borrowed from the computer world, they are IC coolers, and work perfectly with the 2W load each of the LynkLabs modules is generating.

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