Laser cutting on 20mm thick acrylic can be very tricky, and the slightest fault can be clearly seen from the results. Take for example the above image, we can see that there are slight surface scratches due to bad handling of the acrylic.
There is also a slide protrusion at the edge of the inner circle of the letter ‘d’. This is the starting point of the laser. As a rule of thumb, all starting points should begin at an edge in order for them to not be so noticeable, bearing in mind that company signages are all about corporate image.
Also, at such thickness, even the laser’s power output and mirror angles comes into play. It might seem fine on a 5mm piece of material, but when it’s four times the thickness, a slanted laser beam would result in about a 5 degrees variation, and would be especially obvious when placed alongside a right angled edge.