Dear 龚 文益,
Thank you for contacting us.
Currently, you can set the size of characters using the
font-size property of the text class: https://developer.myscript.com/docs/interactive-ink/1.2/reference/styling/#text
You can find the way to proceed in the following post: https://developer-support.myscript.com/support/discussions/topics/16000024177
Let us know if you have further questions.