Using a desk lamp alone is not necessarily bad for your eyes, as long as it is used properly.

It's important to position the lamp in a way that minimizes glare and shadows, and to ensure that the lighting is bright enough for the task at hand without causing eye strain or fatigue.

However, if the lamp is used improperly or positioned too close to the eyes, it can cause eye strain, fatigue, and other discomfort.

It's generally not recommended to leave a desk lamp on overnight, as it can waste energy.

If you need a light source for overnight use, consider using a night light or low-wattage lamp instead.

To light your desk, use a desk lamp that provides ample and adjustable lighting to avoid eye strain.

The lamp should be placed in a position that does not cast shadows on your work area.