Bald Caped Man Elementary School Math Ruler

The angle ruler is hollow, and the front and back scales are gold. There are pictures of bald men, and some formulas and mathematical formulas commonly used by primary school students are added.
After studying for 3 days, I can only draw but not circuit diagrams. Let me talk about some of my drawing experiences:
 
1. Pictures are usually printed on the silk screen layer, not on the solder layer. As long as there is nothing in the solder layer, there will be nothing. lead.
 
2. When the board is white, the color of the silk screen layer will automatically turn to black, which looks better at this time.
 
3. The PCB board is a multi-layered board. If you want to appear golden, you actually need to expose the copper layer in the middle. That is to say, you need to engrave words on both the top layer and the top solder mask layer, and the words need to overlap. The bottom is exposed.
 
4. If the picture to be posted is a real person picture, then first find any photo editing software (such as the Paint that comes with Windows or the Preview that comes with Mac), adjust the saturation to 0, the contrast to 30, and then import it to the circuit board. The time tolerance can be adjusted to 0.1.
 
5. If the picture you post is an animated picture, then directly find a png2svg online conversion website and convert the picture into one color svg (that is, pure black line svg), so that you can see the silhouette effect in this ruler.
 
6. If you want some animation materials, in addition to looking online, you can also buy them on Taobao. I bought more than 100 png pictures with the background removed for 7 yuan.