Ubuntu12.10 screen brightness adjustment experience

I have been using Ubuntu. At the beginning, I don't know that the screen brightness of Ubuntu is too bright. Every time I go to XP in the school room, I think the desktop is too ugly (caused by brightness) ^-^. these days I discovered that my eyes sometimes couldn't stand it. I found out that the screen was too bright when I checked it online. As a result, I started to find this problem, and I had to find a solution every time I started my computer. The following is an experience on adjusting the screen brightness at Ubuntu12.10. Find two methods: one is the same modification/s as on the Wiki.

I have been using Ubuntu. At the beginning, I don't know that the screen brightness of Ubuntu is too bright. Every time I go to XP in the school room, I think the desktop is too ugly (caused by brightness) ^-^. these days I discovered that my eyes sometimes couldn't stand it. I found out that the screen was too bright when I checked it online. As a result, I started to find this problem, and I had to find a solution every time I started my computer.

The following is an example of how to adjust the screen brightness in Ubuntu 12.10.

Find two methods: one is the same as on the Wiki.

Change/sys/class/backlight/acpi_video0/brightness. The tool laptop_mode is also used. It may be because my computer is too strange (Acer aspire 4750g. Original Linpus linux, ora modified version, Windows 7 has not been certified successfully) these two methods are invalid. Every time I modify the above file, it does not change after I restart it. However, I found that my/sys/class/backlight has three directories (as shown below). After opening them, the files are similar and all three files are available: actual_brightness, brightness, and max_brightness. I changed the value of the brightness file in the three folders, and changed the value of the brightness file under the two acpi_video files to 2 (0 ~ 9 (in max_brightness), and change the value of the brightness file under intel_backlight to 400 (0 ~ 976 (also in max_brightness), after restarting, it turns out that the screen is dimmed !!!

It can be seen that the files in the intel_bright directory control the brightness of my screen, rather than the brightness under acpi_video. Therefore, you should not change the brightness under acpi_video in the event of such an egg pain, you also need to check what directory is under the/sys/class/brightness directory, and then change it together. For example, in/etc/rc. add echo 2>/sys/class/backlight/acpi_video0/brightnessecho 400>/sys/class/backlight/intel_video/brightness before exit 0 in local. this is the last script executed before ubuntu is started. If you change the script successfully, the screen is suddenly dimmed at the last second of the boot screen.