Laser cutting technology is extremely versatile, and can cut a wide range of substrates. There are two types of actions that a laser can perform known as vector cutting and raster engraving. The MultiCam 2000 series laser has the ability to execute these functions simultaneously. Vector cutting is simply cutting the outline of a shape or lines on a piece of material. Raster engraving involves the laser performing an engraving function as it moves across the material. There are also two types of imaging used in the respective laser functions called vector imaging and raster imaging. From a design perspective it is very important to understand the types of images you are working on because it will have implications not only for the design software you use, but also the cut you are performing. Let’s take a closer look at each of the functions that can be performed by a laser machine and the great potential these it has to take your production to the next level.
Vector cutting performs the action of cutting an outline and a shape from a piece of material. The word vector itself essentially means “line”. Therefore the designing and cutting process relies on lines to create the desired output.
This type of cutting must be done using a vector image. A vector image consists of geometric formulas that describe the shape or lines it is composed of. This means that instead of being composed of pixels that may not provide as high quality resolution it is composed of pure mathematical formulas. This means that as the image is modified to have a different size or orientation the formulas stay the same and the image keeps its core properties intact. For this reason these images are popular for many computer aided design and manufacturing applications. In addition to consisting of geometric formulas denoting specific lines, vector images can also be edited to embody certain attributes such as fill and colour.
Vector cutting uses the laser to trace the vector lines provided by the vector image to cut the design out of the material. The laser starts at a predetermined point, and continues along the course of the line until the shape has been cut out. Thus this machine provides a valuable function for sign makers and those working with digital graphics because it allows designs to be cut out of a wide range of substrates with the high accuracy and quality that is provided by vector cutting.
Raster engraving involves the laser performing a printer-like function. It moves back and forth across the material while the laser engraves a surface image. For raster cutting either a raster or a vector image can be used. A raster image, also known as a bitmap image consists of small dots called pixels that have a specific colour value assigned to them. The resolution of this type of image is denoted by dots per inch (dpi) or pixels per inch (ppi). Therefore raster images are resolution dependent meaning that as the size increases or decreases the quality of the image is affected. When it comes to photographic images or images high in detail, special effects and shading, raster graphics provide the detail that vector images consisting of lines cannot. A vector image can also be used for raster engraving, but it must have a fill rather than consisting solely of outlines in order to be engraved.
To raster engrave a piece of material the laser cutter will work from top to bottom. Starting at the top it will move from right to left as it advances down the material. As it moves across the material the laser performs its engraving function by changing the surface of the material under the focal point. This is achieved by the material surface being heated by the laser and either fragmenting and detaching from the rest of the surface or by vapourizing the material at that spot on the material. The result is an engraving that captures the high level of detail present in the raster image design. This function is very useful for any company in the digital cutting or sign industry as it opens a wide range of opportunities for new applications and dynamic designs. Not only does the laser provide a way for your to cut material, but through its raster engraving function it allows you to add design and detail to the surface of substrates.