Lighting is very important for work and aids you in getting tasks done.  Some people find it hard to balance between lighting that is too strong or too weak.  Some people will even shift their office desk around to try and find the right lighting for them to work in.

If your lighting is poor:

If the lighting is not evenly distributed across your office desk then as the day draws in you will start to notice the items on your office desk casting shadows.

Watch out for straining to read a document and if your eyes are constantly adjusting from dark to light then you are going to get eye strain.

If your lighting is too bright:

Too much light will mean that your monitor screen may start to glare which leads to eye strain.

If you are moving your office furniture around to accommodate the lighting you may also be adopting bad posture to strain from it which will also lead to lower back and neck strain.

Adjusting lighting to make it brighter:

Make sure your whole work area is illuminated – you need even lighting that comes from the ceiling, if you work at home and the space is small then a lamp on your office desk will do a better job than overhead lighting which may prove to bright for a smaller room.

If there are shadows across your office desk add an additional light to your desk.