Rapid Prototyping Techniques: Taking A Look At The Basics, Advantages And Limitations Of Stereo-Lithography (SLA)

Gone are the days where parts need to be ordered and assembled from assembly lines. Instead, rapid prototyping in the health care industry has focused on numerous techniques that create the customized materials, tools and equipment needed in a matter of minutes. Stereo-lithography (SLA) is one of the most sought after technique. Although equipment that is needed for SLA can cost approximately $1 million apiece, the technology can produce customized products in an efficient manner.

What Is Stereo-Lithography (SLA)?

Stereo-lithography is still fairly new technology in the medical and health industry although many large pharmaceutical and medical companies have quickly caught on to its benefits and have begun investing in improving its design and function. SLA relies on selectively polymerizing a photosensitive type of resin using ultraviolet light. The resin is contained in a vat, and the top layer is subject to ultraviolet light exposure. 

To customize the shape and design of the resin that polymerizes, the ultraviolet light laser beam is moved on the horizontal X and Y-axis. A platform attached to the cured layer of resin is lowered, and a fresh layer of resin is poured over the cured layer and cured to achieve the height desired. 

What Are The Advantages?

Thanks to the achievements of SLA, scientists and medical professionals are able to rapidly manufacture and product prototypes. For rapid prototyping, SLA offers numerous advantages, including:

  • exceptional accuracy. The ultraviolet light laser beam is precise and accurate when curing resin. As a result, the products are accurate replicas of the design blueprint that was inputted into the system. SLA ensures that high quality medical tools and equipment are produced making it perfect for producing customized medical aids.
  • capable of high details and thin walls. One of the largest problems that plague companies manufacturing and producing medical tools is the ability to achieve high detail and also thin walls. As a result, a lot of medical tools and equipment on the market today are quite chunky. SLA can achieve the results needed with ease, and does not require a lot more effort and work to be put in.
  • good surface finish.

The photosensitive resin that is used is extremely durable, and capable of tolerating extreme wear. Most of these polymers are also resistant to chemicals, and can be used in various applications. 

What Are The Limitations? 

As SLA is still fairly new, there are still some aspects of this technology that has yet to be perfected. If you are interested in investing in the equipment needed for SLA, which is quite a huge sum of money, you should familiarize yourself with the limitations of the technology. Limitations include:

  • limited type of materials that can be used. SLA can only polymerize photosensitive resin polymers. 
  • requires post-curing. Depending on the type of design and structure that is desired, a sufficient amount of post-curing time may be needed.
  • support structures are always needed. The photosensitive resin cannot support itself. As a result, support structures are always needed to create the shape desired. While the support structures can be removed later on, this can be a difficult process to achieve. 

Since SLA is fairly new, many companies are looking to improve its design and function in an attempt to solve the limitations that it has. 


Rapid prototyping from companies like EIGERlab has opened doors in the medical industry, and unveiled numerous possibilities for researchers, medical professionals and scientists. SLA is a wondrous technique that has allowed for the prototypes of numerous medical tools and equipment to be produced, and as a result, patients receive higher quality medical care with tools that are customized to their needs.