1688491417109196800

archive/threads/NOTimothyLottes/2023-08-07-crt-emulation-on-lcds-can-be-hard-for-example-its/2023-08-10-BlurBusters-very-interesting-crosstalk-from-voltage-inversion.md

@@ -7,8 +7,8 @@ author: "Blur Busters"
 handle: BlurBusters
 post_id: "1689479056448684032"
 date: 2023-08-10
-archived: 2026-08-23
-draft: true
+archived: 2026-08-25
+draft: false
 tags:
   - archive
   - twitter
@@ -31,8 +31,31 @@ parent_post_id: "1688491417109196800"
 @NOTimothyLottes Very interesting "crosstalk from voltage inversion" artifact. Some repeating patterns or flicker patterns can trigger crosstalk artifacts too. Behavior varies a lot between TN, IPS, and VA, but all of them have to alternate voltage polarity spatially and temporally.
 
 ![](https://pbs.twimg.com/media/F3I8AZmW0AEy6jn?format=png&name=orig)
-
 ![](https://pbs.twimg.com/media/F3I8BVlXoAAnuJB?format=png&name=orig)
+
+**2/**
+
+@NOTimothyLottes Related reads:
+https://www.lagom.nl/lcd-test/inversion.php
+https://forums.blurbusters.com/viewtopic.php?t=7539
+http://www.techmind.org/lcd/#:~:text=Inversion
+
+**3/**
+
+@BlurBusters I appreciate the links. Came to the same conclusion, for LCDs when doing low scaling like 1:2x2 'CRT' emulation, I'll have to do a stylized blue noise phosphor pattern instead.
+
+**4/**
+
+@NOTimothyLottes @BlurBusters "VCOM inversion" -if wasn't line2line but frame2frame that'd "flicker" instead at half the refresh rate so that's why it's preferred& there's also another peculiarity of this scheme. Worth looking into, spent a few hours afternoon,it's late evening now maybe share another time.
+
+**5/**
+
+@Ak4115x @NOTimothyLottes Inversion algorithm is both spatial and temporal on all of them, regardless of spatial pattern of voltage inversion. Line to line is also frame to frame. (lines swaps voltage polarity in next frame)
+
+**6/**
+
+@BlurBusters @NOTimothyLottes LCOS has singular VCOM there's no pattern to it and no such artifact.
+
 ## Related
 
 - Spine: [[archive/threads/NOTimothyLottes/2023-08-07-crt-emulation-on-lcds-can-be-hard-for-example-its]]

archive/threads/NOTimothyLottes/2023-08-07-crt-emulation-on-lcds-can-be-hard-for-example-its/index.md

@@ -7,8 +7,8 @@ author: "NOTimothyLottes"
 handle: NOTimothyLottes
 post_id: "1688491417109196800"
 date: 2023-08-07
-archived: 2026-08-23
-draft: true
+archived: 2026-08-25
+draft: false
 tags:
   - archive
   - twitter
@@ -30,8 +30,8 @@ in_reply_to: ""
 CRT emulation on LCDs can be hard. For example it's often easy to generate a pattern that causes a LCD hardware bug. NOT joking. Here is an example on the Steam Deck. The pattern in the window affects the scan (Deck scan is rotated) outside the window.
 
 ![](https://pbs.twimg.com/media/F265_JZXsAAInpa?format=jpg&name=orig)
-
 ![](https://pbs.twimg.com/media/F265_hLXkAAnfek?format=jpg&name=orig)
+
 Branches: [[archive/threads/NOTimothyLottes/2023-08-07-crt-emulation-on-lcds-can-be-hard-for-example-its/2023-08-10-BlurBusters-very-interesting-crosstalk-from-voltage-inversion]]
 
 **2/**
@@ -39,11 +39,13 @@ Branches: [[archive/threads/NOTimothyLottes/2023-08-07-crt-emulation-on-lcds-can
 The actual pattern is this (it's a 2x1 pixel checker of {G,RB}).
 
 ![](https://pbs.twimg.com/media/F266epnW4AAdCiK?format=png&name=orig)
+
 **3/**
 
 The theory: Deck's 90deg scan results in {(bottom)R, G, B (top)} sub-pixel components. So could alternate {G,RB} only per pixel in a checker pattern to generate a new sub-pixel pattern at a different resolution. In this case trying for 640x400 virtual resolution.
 
 ![](https://pbs.twimg.com/media/F267UYuXAAAO50A?format=png&name=orig)
+
 **4/**
 
 For virtual pixel, shift energy into masked virtual phosphor. So 50% brightness red, would be {100%, 0%} for {in, out} of phosphor pixels. Over 50% one starts to increase non-phosphor pixels until some maximum so mask is still visible, but brightness isn't too compromised.