Choosing the right lamp, shade, bulb

Selecting the right table or desk lamp requires careful thought. The lamp you see in the store may look great but may not work for you. Determine the lamp's use and its location in a room. Also measure the table, the lamp, and the shade before you buy.

Height

If a lamp is too tall, light shines in your eyes while you are trying to read. If it's too short, the light is not spread far enough to illuminate the whole page of your reading material.

The lower edge of the lamp shade should be at eye level. This is generally 44 to 46 inches above the floor if you are sitting at a desk, or about 40 inches above the floor if you are sitting on a sofa or lounge chair.

For a lamp on an end table, measure the height of the table and subtract it from the 40-inch eye level. If you are putting a lamp on a 20-inch-high table, the right lamp should measure 20 inches from the bottom of the shade to the top of the table.

Shades and bulbs

Lighting specialists recommend that the shade measure 16 to 18 inches at the widest point of the bottom edge. If the bulb or bulbs are situated under the shade in the usual base-down position, the socket should be even with the bottom of the shade.

If bulbs are base up or horizontal, the lowest point of the bulb should be no more than three inches above the bottom edge of the shade.

Experts recommend a minimum of 150 watts in any single socket lamp used for reading or sewing.

Three-way 50/100/150-watt bulbs add versatility, allowing lower levels of light when desired. It's best to use three-way bulbs only in base-down position.

In lamps with two or more sockets in base-up or horizontal position, the total should be no less than 120 watts, and at least 180 watts when sockets are in base-down position.

General Electric makes available further information about lamps and lighting in a well-illustrated booklet available for 75 cents from ''The Light Book,'' No. 803-152, Inquiry Department, General Electric Company, Nela Park, Cleveland, Ohio 44112.