<p>I'm surprised your research hasn't answered your question, as the concept is relatively simple. You have most of the answer in the question. The missing item is a light source. Usually the source is an array of ultraviolet LED modules. There are resin printers that would not be called LCD printers, as they use computer display projectors to generate both the image and the UV to cure the resin.</p>

<p>A rather extensive list of various resin printers can be found at <a href="https://www.aniwaa.com/the-best-resin-3d-printer-sla-and-dlp/" rel="nofollow noreferrer">aniwaa.com</a> along with a clear explanation of the technologies.</p>

<p>The image below is courtesy of the link in the previous paragraph.</p>

<p><a href="https://i.sstatic.net/LSzPW.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/LSzPW.jpg" alt="printer diagram"></a></p>

<p>The light source that answers your question is visible in the third picture. As noted, the LCD panel blocks the light based on the image to be cured. I think the "uses its own light" is somewhat misleading, unless the builder has found a high-UV output LED LCD panel or is using daylight resins and has configured for long burn-in times.</p>

CC BY-SA 4.0
2019-04-09T13:53:52.237Z
Ah yes that seems to clarify things. I recently learned LCD displays are transparent until a certain pixel is turned on, in which it blocks out light. If I am correct, an image is generated, and the actual layer is the negative space on the LCD. Then the UV LED array cures the resin via the open pixels on the LCD
1Ghasthunter1
CC BY-SA 4.0
2019-04-09T14:10:19.863Z
University of Michigan has the ability to do something where they use different kinds of UV light + lasers to better control exactly when hardening happens and to penetrate into the material and cure multiple layers (up to about a millimeter) at once. Prints come out in a matter of minutes.
Joel Coehoorn
CC BY-SA 4.0
2019-04-08T01:15:06.363Z
2019-04-09T07:49:29.320Z
2019-04-09T07:49:29.320Z
fred_dot_u
<p>I've been wondering this for a while, and have searched for hours and have found nothing except undetailed explanations and projects.</p>

<p>How does a UV LCD 3D resin printer cure resin exactly? I understand there is an LCD screen, but where does the UV light come from? Where is it placed?</p>

CC BY-SA 4.0
2020-04-21T02:17:26.683Z
Carl, It's a year later, but I think that my question is pretty simple, especially since I clarified it in the second part of the question.
1Ghasthunter1
CC BY-SA 4.0
2019-04-08T15:22:57.477Z
You should clarify your question.  Do you want to know how the light is directed where it's wanted, or do you want to know how resins change state under the influence of photons?
Carl Witthoft
<sla><knowledgebase><resin>
How does a UV LCD 3D resin printer work?
1Ghasthunter1
# How does a UV LCD 3D resin printer work?

(Asked by: username_0 on 2019-04-08)

I've been wondering this for a while, and have searched for hours and have found nothing except undetailed explanations and projects.

How does a UV LCD 3D resin printer cure resin exactly? I understand there is an LCD screen, but where does the UV light come from? Where is it placed?

**Tags:** sla, knowledgebase, resin
> **Comments:**
> **username_1**: You should clarify your question.  Do you want to know how the light is directed where it's wanted, or do you want to know how resins change state under the influence of photons?  
> **username_0**: Carl, It's a year later, but I think that my question is pretty simple, especially since I clarified it in the second part of the question.  

---

## 1 answers

### Answer by username_2 on 2019-04-08. Score: 9 | Accepted answer

I'm surprised your research hasn't answered your question, as the concept is relatively simple. You have most of the answer in the question. The missing item is a light source. Usually the source is an array of ultraviolet LED modules. There are resin printers that would not be called LCD printers, as they use computer display projectors to generate both the image and the UV to cure the resin.

A rather extensive list of various resin printers can be found at [aniwaa.com](https://www.aniwaa.com/the-best-resin-3d-printer-sla-and-dlp/) along with a clear explanation of the technologies.

The image below is courtesy of the link in the previous paragraph.

[![printer diagram](https://i.sstatic.net/LSzPW.jpg)](https://i.sstatic.net/LSzPW.jpg)

The light source that answers your question is visible in the third picture. As noted, the LCD panel blocks the light based on the image to be cured. I think the "uses its own light" is somewhat misleading, unless the builder has found a high-UV output LED LCD panel or is using daylight resins and has configured for long burn-in times.

> **Comments:**
> **username_0**: Ah yes that seems to clarify things. I recently learned LCD displays are transparent until a certain pixel is turned on, in which it blocks out light. If I am correct, an image is generated, and the actual layer is the negative space on the LCD. Then the UV LED array cures the resin via the open pixels on the LCD  
> **username_3**: University of Michigan has the ability to do something where they use different kinds of UV light + lasers to better control exactly when hardening happens and to penetrate into the material and cure multiple layers (up to about a millimeter) at once. Prints come out in a matter of minutes.  

---

