3D printing is becoming more and more popular. When it comes to light-curing 3D printing, most people may only know the molding method of sla, but they also think that this kind of printer should cost tens of thousands of yuan. When the name of light-curing is heard, it will be cured by light The meaning of molding.
Most of the consumables used for photocuring are photosensitive resins, which are a mixture of photoinitiators, monomer polymers and prepolymers. This material can be cured under specific wavelength UV light focusing.
Now photosensitive resin materials are generally used in SLA, DLP, and LCD models. The model printed with photosensitive resin material has a smoother surface, high printing accuracy and high molding quality.
The core of every light curing technology is a solution to the problem of light source, from the SLA of laser scanning, to the DLP of digital projection, to the latest LCD printing technology. We can understand the characteristics of light curing technology. Light curing technology, in addition to SLA laser scanning and DLP digital projection, has formed a new technology that uses LCD as a light source. The simplest understanding of LCD printing technology is that the light source of DLP technology is replaced by LCD.
Thirty years ago, when 3D printing came out, it started with light curing technology SLA (laser scanning) stereolithography technology. So light curing is the boss of 3D printing technology. LCD mask technology has been developed since 2013. If you are interested, you can find the earliest makers used ordinary computer LCD monitors to remove the backlight board, and add 405 LED lamp beads as backlight, and try to print uv resin.
Next, I will give you a detailed introduction to the forming principles of the three machines.
LCD is the abbreviation of Liquid Crystal Display. As the name implies, it is a liquid crystal projector. It is a three-color liquid crystal panel of red, green and blue, which is magnified by a lens and transmitted through a mirror. The light source in the LCD projector is a metal halide lamp or UHP (cold light source).
DLP is the abbreviation of “Digital Light Processing”, that is, digital light processing, that is, the image signal must be digitally processed before the light is projected. The principle is to pass the cold light source emitted by the UHP bulb through the condensing lens, homogenize the light by Rod (light rod), and pass the processed light through a color wheel, dividing the light into RGB three, (or RGBW Wait for more colors), and then project the color on the DMD chip by the lens, and finally reflect the image on the projection screen through the projection lens.
SLA is the abbreviation of “Stereo Lithography Apparatus”. The laser beam outlines the shape of the first layer of the object on the surface of the liquid photosensitive resin, and then the production platform is lowered a certain distance, and then the cured layer is immersed in the liquid resin. This is repeated until the printing is formed. Finally, after the prototype is taken out of the resin, it is finally cured, and then polished, electroplated, painted or colored to obtain the required product.
In addition to light curing technology, the core problem of light source, there are many supporting problems in software, automation, application and industry. Another core issue, light curing resin, is also a core technology.
From the perspective of the principle of light curing rapid prototyping and the materials it uses, light curing rapid prototyping has the following characteristics:
Advantages of SLA processing: