The TI-85 is a graphing calculator made by Texas Instruments. One of the settings on the TI-85 allows you to adjust the contrast on the screen. When you battery runs low, the calculator display may dim, so you have to increase the contrast. However, when you replace the batteries, you may find that you want to lighten the screen. As long as you know which keys to press, you can quickly and easily make the change.
Push the "2nd" key on the TI-85.
Push and hold the down triangle key on the directional keypad to decrease the contrast.
Release the down triangle key when you have lightened the screen enough. The longer you hold down the key, the less contrast the screen will have.