# How to set the gamma?

I have a TFT 2.2 inch Display. like this:

Its controller is ILI9341. I ported it to my MCU and everythings work fine. one of the most important things in using a display is Gamma. when you would use a display you have to adjust it because it effects on the brightness. I think I have to adjust the Gamma of my display. the value that currently I use for Gamma is 0x01. I think that's the default value. when I looked at the datasheet. unfortunately as I expected that's weird to me. :(

also I have searched for finding a solution but none of the results was good. I have converted some part of the datasheet to jpeg for you that are about Gamma. links:

How can I adjust the Gamma with these datas? there is an equation, When should I use it? how can I use it? What's positive and negative Gamma?

Added1: For supply I use 5V for Vcc and 3.3V exactly.

Added2: two pictures of my LCD when show me 0x001F (blue) color in 16bit (65,536 colors) mode.

• Why not just try some of the values for + an - correction in section 14 of the doc you provided, and see what they do? – Scott Seidman Feb 6 '15 at 13:51
• @ScottSeidman Umm...okay, but I'm curious to know more about Gamma. – Roh Feb 6 '15 at 16:35