The Intricate Process of Creating Custom Glass Gobos

The first step in creating a custom glass gobo is the design. High-quality artwork is crucial. It should be in the correct size, format, and resolution. Most designers prefer using vector-based software like Adobe Illustrator (AI) or Encapsulated PostScript (EPS) format. These formats ensure that the design can be scaled without losing its clarity. For example, if a client wants a custom gobo with their brand logo, the designer will take the logo file and optimize it for the gobo production. The design should be simple yet impactful, as overly complex designs may not translate well during the etching or laser-cutting process.​

For glass gobos, borosilicate glass is a popular choice. It has excellent heat-resistance properties, which is vital when used in lighting fixtures. The thickness of the glass also matters; typically, a thickness between 1 - 3 mm is used, depending on the specific application and the type of lighting fixture. A thicker glass may be more suitable for high-powered projectors where there is more heat generation.​

• Etching Process:​

If the design requires a more detailed and precise finish, chemical etching can be used. First, the design is transferred onto a film using super-high-resolution imagesetters. For full-color glass gobos, the image is separated into CMYK layers and exposed separately onto extremely thin pieces of dichroic glass. Then, the glass is processed with a positive resist developer, followed by the use of acid to remove the coatings. After that, it is cleaned with acetone, dried, and inspected. This process is time-consuming but results in a very high-quality finish, ideal for detailed artistic designs or photographic images.​

• Laser-Cutting Process:​

Laser-cutting is another method for creating glass gobos. A dedicated laser software draws precise outlines around the artwork file. The data is then sent to the laser, which cuts or engraves the design onto the glass. The glass gobo material is placed into a holder, and the laser works its magic. This method is faster than etching for simpler designs and can be used to create both monochromatic and grayscale gobos. However, it may not be as suitable for highly detailed full-color designs as chemical etching.​

Once the gobo is created, it undergoes strict quality control. Quality control experts check for any imperfections, such as scratches, uneven etching, or incorrect sizing. They also test the gobo in a sample lighting fixture to ensure that the projection is clear and accurate. For example, they will check if the logo projected is sharp and free from any distortion. Only gobos that meet the high-quality standards are approved for shipment.​

After passing the quality control, the glass gobo is prepared for shipment. It is carefully mounted in a suitable holder, depending on the type of lighting fixture it will be used with. For some fixtures, a metal bezel may be added to secure the gobo in place. The gobo is then packaged in a protective box to prevent damage during transit.​