I ran into a problem when I used Gazebo to simulate the Projector I added

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I added a Projector to Gazebo and ran into a problem during the simulation.

There is a ball right under the projector.The simulation results are somewhat different from the real world.
Even the lower half of the ball is projected.The texture of the projection is a checkerboard image
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Here is my projector’s model.sdf

<?xml version="1.0" ?> 0 0 3 0 0 0 false true 0.1 0.3 0.1 0.1 0.3 0.1 0 0 2.9 0 0 0 1 1 1 checker_rgba.png 0.159931088597 0.1 100 true