关于笔记本linux亮度调节

Laptop安装linux系统后，开机默认亮度是最大，每次开机都很刺眼，开机后调节好亮度后，重启又恢复了。现在介绍可以永久设置屏幕亮度的方法，这样就不用每次开机都设置亮度那么麻烦。

调节亮度的方法是：Fn+左右键

首先查看自己的显卡亮度控制文件是哪种

ls /sys/class/backlight/

一般没有独显的电脑显示的是acpi_video0

有独显的电脑则显示intel_backlight

如果亮度控制文件是acpi_video0

打开/etc/rc.local文件

sudo vi /etc/rc.local

在exit 0前一行加入如下代码

echo 0 > /sys/class/backlight/acpi_video0/brightness

保存退出，重启就可以了

其中echo 后面的值为0-10，对应为0到100%,如echo 5表示一半亮度

如果亮度控制文件是intel_backlight

首先修改grub

sudo gedit /etc/default/grub

把GRUB_CMDLINE_LINUX=""改为GRUB_CMDLINE_LINUX="acpi_backlight=vendor"

修改后文件代码如下

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
#   info -f grub -n 'Simple configuration'

GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX="acpi_backlight=vendor"

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"

更新grub.cfg

sudo update-grub

修改亮度文件，方法和没有独显的电脑一样

sudo vi /etc/rc.local
echo 150 > /sys/class/backlight/intel_backlight/brightness

保存退出，重启就可以了

注意这里echo后面的数值和没有独显的不同，具体自己调一下看看

调节方法是进入root模式调节

sudo su
echo 150 > /sys/class/backlight/intel_backlight/brightness

不断修改echo后面的值找到最适合的值