The Unity launcher is the vertical bar with icons on the left side of your Ubuntu desktop. It allows you to easily launch programs and to access workspaces, removable devices, and the trash bin. Initially, the Unity launcher icons are fairly large.
Unity启动器是Ubuntu桌面左侧带有图标的垂直条。 它使您可以轻松启动程序并访问工作区，可移动设备和垃圾箱。 最初，Unity启动器图标很大。
However, if you work on a smaller screen, you may want to decrease the size of the icons. Or, you may want to increase the size of the icons to make them easier to click if you have a large screen or multiple screens. This is easy to do, and we will show you how.
但是，如果您在较小的屏幕上工作，则可能需要减小图标的大小。 或者，如果您有大屏幕或多屏幕，则可能需要增加图标的大小，以使其更易于单击。 这很容易做到，我们将向您展示如何做。
Click the System Settings icon on the Unity launcher.
单击Unity启动器上的系统设置图标。
NOTE: You can also click the gear in the upper-right corner of the screen on the top bar and select System Settings.
注意：您也可以单击顶部栏屏幕右上角的齿轮，然后选择系统设置。
On the Settings dialog box, click Appearance in the Personal section.
在设置对话框上，单击个人部分中的外观。
On the Appearance screen, make sure the Look tab is selected.
在外观屏幕上，确保选择了“外观”选项卡。
In the bottom-right corner is a slider for changing the Launcher icon size. Drag the marker either direction to increase or decrease the icon size on the Unity launcher. You can see the results on the Unity launcher as you change the size.
右下角是一个用于更改启动器图标大小的滑块。 沿任一方向拖动标记以增加或减小Unity启动器上的图标大小。 更改大小后，您可以在Unity启动器上查看结果。
To close the Settings dialog box, click the X in the upper-left corner.
要关闭“设置”对话框，请单击左上角的X。
The Unity launcher icons have been made smaller in the image below.
下图使Unity启动器图标变小了。
The default size of the Unity launcher icons is 48 in case you want to go back to the original size.
如果要恢复为原始大小，Unity启动器图标的默认大小为48。
翻译自: https://www.howtogeek.com/188096/how-to-resize-the-unity-launcher-icons-in-ubuntu-14.04/