3 Types of Computer-to-Plate Methods

Making the switch to a new plate might be a solid financial option and benefit CTP production.

Businesses worldwide continue transitioning to digital technologies. The printing industry is no exception. And as the demand  for Computer-to-Plate (CTP) technology continues increasing, equipment manufacturers — including the big brands such as Screen, Fuji,  Agfa and others — are expanding product lines and introducing new CTP plate offerings to the marketplace.

As more choices become available,  it makes purchasing decisions for company owners more complicated.

CTP methods and models differ based on imagesetters’ construction, including  three different types of critical parts: — an internal drum, external drum and flat-bed imagesetters — and the light source used to expose plates’ surfaces.

Here are the key differences

Internal Drum Imagesetters

With an internal drum imagesetter a fixed plate is placed into a cylinder and the imaging head moves along the axis of the cylinder to expose the plate. A rotating mirror at the end of the imaging head rotates around the axis to beam the laser onto the part of the plate duplicating the image. Internal drum imagesetters can increase the difficulty of use several lasers simultaneously. However, using one laser also provides its unique advantages, primarily exposing uniform light intensity over the entire plate during the imaging period.

External Drum Imagesetters

External drum imagesetters are known for their simple construction type which allows operators to  arrange multiple image heads next to each other and use them at the same time. With this method, the plate wraps around a drum which  rotates around its axis, while the imaging head — the part which  projects images onto the plate —moves along the axis focusing the laser beam onto the plate’s surface. This sort of productions decreases the process time required to expose the printing plate(s).

Flat-bed Imagesetters

This technology reproduces the image  line-by-line onto a fixed, flat printing plate from a laser beam which first deflects the light source with a rotating polygon mirror and then does the same onto the printing plate. The setup of this type of laser beam can provide less accuracy at the edges of the printing plate and as a result is more common for printing smaller formats or any type of  image where lower quality expectations are acceptable.

The Takeaway

Any CTP offers printers many benefits. Among them, CTPs increase the sharpness of images, eliminates defects in the plates caused by scratches from emulsion and dust on the film, streamlines film exposure and processing and can reduce costs and daily management functions of film processing and overall production.

Of course, like any product, there are also disadvantages. If any CTP plate becomes damaged, it needs to be replaced and the  process must be repeated.

Platesetters.com carries not only different types of refurbished imagesetters, but also typically stocks  top brands and offers worldwide shipping. In addition, Platesetters’ factory-trained technicians provide routine maintenance, onsite repair and remote service to keep your CTP devices in top condition, so your business doesn’t  experience productive downtime, upset customers, or profit loss. Platesetters also  stands behind its work by providing one of the industry’s  best warranties. Check out platesetters.com today, call (888) 380-7483, or email us for more information about our products and services.

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