Yealink T4 Series IP Phones User Guide102Active Level: The brightness level of the phone screen when the phone is active. Digits 1 to 10 represent differentbrightness levels. 10 is the brightest level. It is only available for the T48S/T48G/T46S/T46G phone.Inactive Level: The brightness of the phone screen when the phone is inactive. You can select a low brightness or turnoff the backlight. It is only available for the T48S/T48G/T46S/T46G phones.Backlight Time: The delay time to change the brightness of the phone screen when the phone is inactive. Backlighttime includes the following settings:l Always On: Backlight is on permanently.l Always Off: Backlight is off permanently. It is not available for the T48S/T48G/T46S/T46G phone.l 15s, 30s, 1min, 2min, 5min, 10min or 30min: Backlight is changed when the phone is inactive after the designatedtime.Procedure1. Navigate to Menu > Basic > Display > Backlight.On the T42S/T42G/T41S/T41P/T40P/T40G phones, navigate to Menu > Settings > Basic Settings > Display > Back-light.2. On the T48S/T48G/T46S/T46G phones, select the desired level from the Active Level field.3. On the T48S/T48G/T46S/T46G phones, select the desired level from the Inactive Level field.4. Select the desired time from the Backlight Time field.5. Select Save.Adjusting the Screen ContrastYou can adjust the screen contrast of the phone to make it easier to read.The intensity of screen contrast ranges from 1 to 10 and the highest intensity is 10. It is only available for the T40P/T40Gphones.Procedure1. Navigate to Menu > Settings > Basic Settings > Display > Contrast.2. Select the desired value from the Contrast field.3. Select Save.Changing the LanguageYour phone supports several languages that you can choose to use on the phone.Contact your system administrator to find out exactly which languages are supported on your phone.NoteThe T48G/T46G/T42G/T41P phones do not support French (Canada), Portuguese (Latin) and Spanish (Latin).Procedure1. Navigate to Menu > Basic > Language.On the T42S/T42G/T41S/T41P/T40P/T40G phones, navigate to Menu > Settings > Basic Settings > Language.2. Select the desired language.3. Select Save.The phone language is changed to the selected one.