Overview

A pen display will either one of two surfaces:

• Etched glass - glass that has an etched texture. Learn more here: etched glass

• Film - A thin film on plastic that sits on top of the glass. See anti-glare film.

The traditional thinking is that etched glass is better. You will see many "pro" tablets that have etched glass while their "consumer" counterparts have the film.

My view is that it is not so clear that etched glass is better. In some cases films have real advantages. In this document we'll discuss the merits of each.

Anti-glare sparkle

AMOUNT of Anti-glare sparkle - which is an undesirable effect - is present in both etched glass and films. And the amount is highly variable. It's not possible to say that either choices has less of the sparkle. You have to examine the specific etching or film used for a tablet.

Changing the etching

This is not possible. There is no known way to reduce the amount etching on glass.

Removing and replacing the film

For films, many tablets that do have films have removable films. And manufacturers even sell replacement films.

This is one flexibility that films have over etching.

• You can remove the film entirely

• If you scratch the film, you can replace the film.

• If you don't like some aspect of the film - maybe it has too much AG sparkle - you can buy a different film that has different properties. For example, Photodon sells films that have different amounts of AG effects. You can even get completely clear film.

NOTE: Some pen displays have very securely attached films, and it may be difficult to remove them.

Handling scratches

• Scratches in etched glass are permanent

• Films are clearly better at this since the films can be replaced.

Texture

Plain glass will feel slippery to draw on. Etched glass offers some texture and so too do films - so you will find that your pen grips the surface a bit better.

In my opinion the etched glass has a silghtly stronger texture feeling. The films tend to fill a little different. Both are better than plain glass.

Companion video

Because this is a visible phenomenon, watching the video I made on this topic may be a good starting point. https://youtu.be/g_nsvraK3P8

Reducing the anti-glare sparkle

Overview

To prevent reflections and room lighting from interfering with your drawing experience, manufacturers of pen displays provide an anti-glare treatment.

The treatment comes in two forms:

• anti-glare etched glass

• anti-glare film

The physics of the anti-glare treatment produces an effect called anti-glare sparkle (AG sparkle).

AG sparkle is hard to describe in words, but overall it will look like a grainy look.

What it looks like

Photographing it or filming it is very tricky.

Depending on the camera settings...

• the effect can disappear

• the sparkle can look very different from what your eyes see.

• you might notice it more with some colors than others

Example 1

The the pictures below show screens that are showing black, white, and gray pixels.

The one on the right represents an mor extreme example . You can clearly see that different "color grains"

Example 2

It could also look like this - this is a very close up view

Example 3

I found this in a reddit post. The AG sparkle is everywhere but is most noticeable in the green area.

How manufacturers refer to the AG treatment

Huion Kamvas Pro 24 (4K) [GT2401]

XP-Pen Artist Pro 16TP [MD160U]

Wacom One [DTC133]

Buying a tablet

You MUST research AG sparkly for any tablet you are intend to buy.

I see many people buy tablets and not realize the AG sparkle might be present. And so they get very frustrated with their purchase.

DO NOT rely on photos provided by the manufacturer. These photos never show AG sparkle. It's probably not even deliberate that AG sparkle isn't shown because it is very tricky to photograph.

You need to ask people who use the tablet if the tablet exhibits the effect and how much the effect is visible.

Prevalence

AG sparkle is varies depending on the model of pen display.

All pen displays that I know of will have some amount of it because they all have some kind of anti-glare treatment.

Contributing factors

Your perception of AG sparkly will be affected by several factors.

• The nature of anti-glare treatment. Some tablets models in general seem to use a very intense AG treatment and others have a much milder treatment.

• The distance between your eyes and the tablet. What might be strongly noticeable at 1 few inches might be essentially invisible at a normal drawing distance.

• The pixels-per-inch (PPI) of the display.

High Pitch (PPI) displays

High-pitch means lots of pixels per inch (PPI).

For example:

• 4K on a 27" pen display has a pitch of 163.7 PPI

• 4K on 16" pen display gives a pitch of 281.4 PPI

AG Sparkle will appear more on high-pitch displays

If the same exact AG treatment is used on those two displays you will notice it more on the 16" display.

Removing the Anti-glare sparkle

AG Etched Glass

I don't know of any way to remove the anti-glare sparkle if it is due to etched glass.

However, some people have had luck reducing the sparkle by adding a film on top of the AG glass.

Here is an example:

• r/wacom - Cintiq 24 Pro OEM screen protector 6/9/2023

AG Film

Tablets with replaceable AG films

Some tablets have a film that is designed to be removed and replaced. For example the Huion Kamvas 13 https://www.youtube.com/watch?v=B8CyIZfX8co. If you have such a tablet you could remove the film.

You could also try 3rd party screen protectors to replace the one you have. See protective sheets.

Tablets without replaceable AG films

If the tablet's film is not designed to be removed, you could still do it, but I think you might risk damaging the glass. If you do pursue this route, try to find someone who did this before and learn from their experience.

Removing the AG film without replacing it

If you do remove the film, you will be drawing on the glass of the display. To avoid scratching that glass, you may want to search for a film that can protect it, but that does not have any anti-glare treatment. See protective sheets.

Reddit threads

• r/huion - https://www.reddit.com/r/huion/comments/13ikmph/ - This deleted reddit post has an video thet perfectly demonstrates the shimmering effect of the sparkle.

• r/huion - Is this normal? Possible display issue? noisy output? 11/23/2022

References

https://www.radiantvisionsystems.com/blog/repeatable-sparkle-measurement-quality-control-anti-glare-displays

https://www.youtube.com/watch?v=8iTGUNAxPOc

https://jamesferwerda.files.wordpress.com/2015/06/j18_ferwerda14_jsid.pdf

Overview

Lamination in the context of a display is the removal of an air gap between the display and the sheet of glass above it. The benefits of lamination are improved parallax and preventing things from getting between the glass and the display.

The air gap

Especially in older models of pen displays and pen computers, there is an air gap between the display panel and the glass. This air gap itself is another source of parallax.

A laminated display removes the air gap and replaced it with an optically clear adhesive layer. This layer because of optical properties and because it can be thinner than the air gap it replaced also thus reduces the parallax.

It is always preferable to by a drawing tablet that has a laminated display.

Benefits of lamination

The most obvious benefit of lamination and the removal of the air gap is that it can improve parallax.

However, it can also prevent a things from getting between the glass and display panel such as:

• moisture

• dust and other particles

Resources

Overview

Drawing tablets that have an embedded display panel and those display panels have maximum typical brightness. You have been exposed to many display panels in televisions in phones and watches. Here I'd like to set your expectations about what you're going to experience in terms of brightness for drawing tablets.

Measurement

Brightness is measured in cd/m2 () but that is hard to type so man people use the equivalent unit of nit.

Lighting conditions

The environment you are using the tablet in greatly affects the brightness you need. Below is my take on what you need under different conditions

What you can expect from drawing tablets

Overall, display panels for drawing tablets fall in the range of 200 to 400 nits.

• Many are within the range 220 to 250 nits.

• Only a few are >= 300 nits.

Distribution of brightness values

Here is the distribution of brightness values for pen displays released on 2020 or later.

Top 10 brightest pen displays

Includes only those pen displays that have been released since 2020

Fan noise

A few tablets (only Wacom as far as I know) have fans. And these fans help to keep their brighter displays cool. The fan noise can be disturbing for some people. For others it doesn't matter.

Overview

Also called "Matte film", anti-glare film glass is one of two popular treatments the glass surface of a pen display. (The other is called ).

This film is affixed to the glass underneath with some optically clear adhesive.

Benefits

Anti-glare film provides two benefits

• It reduces glare and reflections due to light hitting the tablet. The film does this my scattering that light.

• It adds some texture which helps the pen grip better - without this the pen would feel slippery on the glass

• As a film, it provides some protection to the glass underneath.

• Some films are designed can be removed and replaced. So if you've scratched up the film, you can restore the table to its original feeling.

Removal and replacement

For SOME tablets, these films are intended to be removed by the user. Some manufacturers even sell replacement films. These films, tend to be easily removed.

For SOME tablets, these films are quite firmly attached to the glass and are not easily removed.

If you remove the film, you'll notice typically that the display will look brighter and the colors more vibrant, however:

• you'll notice glare

• And of course the glass is no longer protected from scratches

Films are NOT lamination

Sometime people confuse these films with lamination. They are very different and have different benefits:

• These films are on TOP of the glass

• Lamination means that the glass is bonded UNDERNEATH to the display panel

So it is quite possible to have a pen display that has BOTH a film AND is laminated.

Overview

Etched glass is one of two popular treatments the glass surface of a pen display. (The other is called an ).

"Etched glass" describes a microscopic texture applied to a glass surface.

Etched glass provides two benefits

• It reduces glare and reflections due to light hitting the tablet. Etched glass does this my scattering that light.

• Provides more "grip" for the pen. Without the etching a pen would feel "slippery" on the smooth glass surface.

Sparkle

Permanence

Etched glass is a permanent treatment to the glass. It cannot be removed.