There are some good sites to make lithophane from your own image:
This stand is for the Flat Lithophane 100mm width and 4mm thickness.
Its size is 120mm x 30mm x 9mm.
The sloped slot provides stable support for the lithophane.
There are some members who are interested in lithophane than I expected.
So I have attached the example shown in the photo.
There are some tips to print it clearly.
I recommend you to visit the sites above.
And try to print lithophanes with your own images.
The author marked this model as their own original creation.