Plastic light-folding element, imaging lens assembly module and electronic device

A plastic light-folding element, comprising:

• an incident surface configured to let an imaging light enter the plastic light-folding element;
• an exit surface configured to let the imaging light exit the plastic light-folding element;
• at least one reflective surface configured to fold the imaging light;
• at least one connecting surface connected to the incident surface, the exit surface and the at least one reflective surface;
• and
• at least one gate vestige structure disposed on the at least one connecting surface;
• wherein each of the incident surface, the exit surface and the at least one reflective surface comprises an optical portion and an arc step structure, each of the arc step structures is disposed on a periphery of each of the optical portions, and an arc is formed by each of the arc step structures centered on each of the optical portions;
• wherein an area of the at least one gate vestige structure on the at least one connecting surface is Ag, a total area of the at least one connecting surface is At, a step height of each of the arc step structures is h, and the following conditions are satisfied:
• 33%≤Ag/At≤90%;
• and
• 0.003 mm≤h≤0.17 mm.