A typical computer screen produces about 20-25 footcandles (FC) of measured light. To avoid headaches from your eyes dilating back and forth when you switch from looking at your computer to your desk, you want at least a 3 to 1 contrast ratio of light (20-25 FC from your screen, 50-75 on your desk).
Be aware of glare issues. Purchase a task lamp with an adjustable head and arm.
Adults should purchase a high quality fixture (with a dimmer) that will last a lifetime.
The desk lamp should have a dimmer or two position (high – low) switch. Cord dimmers can be purchased for fixtures that do not have dimming options.
The adjustable LED lamp head should be cool to the touch or have a handle that protects you from high heat.