Traditional Culture Encyclopedia - Photography major - What's the name of this shooting technique?

What's the name of this shooting technique?

In complete darkness, open camera door B and keep it open. Write what you want with a small flashlight or pencil, and then close door B. This technology must be tested many times before it can succeed. Fortunately, it is all digital now, and the effect adjustment data can be seen at any time, which is different from the previous film shooting. This technique is "light painting" shooting.