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External blur reduction adapter

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Re: External blur reduction adapter

Postby thatoneguy » 01 Jan 2017, 17:54

All I'm proposing is a port to bypass the circuitry that controls the backlight so you could control it via your own custom external circuitry
It's not a hard concept to grasp

How will it work through USB/HDMI? I don't know...but when you can use USB-C to charge electrical devices I don't see why the same effect can't be done for controlling a backlight

It's such a damn simple concept to grasp yet you still do not grasp it....ugh I'm frustrated :|
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Re: External blur reduction adapter

Postby Chief Blur Buster » 02 Jan 2017, 19:29

thatoneguy wrote:All I'm proposing is a port to bypass the circuitry that controls the backlight so you could control it via your own custom external circuitry
It's not a hard concept to grasp

How will it work through USB/HDMI? I don't know...but when you can use USB-C to charge electrical devices I don't see why the same effect can't be done for controlling a backlight

It's such a damn simple concept to grasp yet you still do not grasp it....ugh I'm frustrated :|

Yes, this will work.

I understand this concept!

Yes, this is definitely possible. However, it requires hardware hacking. Opening up the monitor and hacking a microcontroller (Ardunio, etc) to the monitor's edgelight.

I wrote an article about this:
Electronics Hacking: Creating a Strobe Backlight

Basically, an Arduino-driven backlight power supply with custom strobe capability. You'd also have to wire a VSYNC trigger to one of the Arduino's digital inputs, so that the microcontroller could properly time the strobes (with an adjustable phase offset) relative to the blanking intervals. Then the computer can control the Arduino (e.g. strobe length, strobe phase, etc) over the USB cable. The Arduino would do the strobing itself.

Also, in theory, this could also provide a way to do reliable strobed GSYNC/FreeSync (under certain conditions).

USB is probably not accurate enough to be the strobe timing signal, but it works fine for controlling a tiny box in the middle of the cable, such as an Arduino, which would "do the rest". (In theory, the USB can fine-tune Arduino-driven strobe phase/timing, if there wasn't a reliable VSYNC signal to hook into. The Arduino could intheory extrapolate the exact frequency based on rough/coarse/jittery USB signalling, but this would be much harder than finding a solder joint to wire a digital VSYNC trigger to)

A few people who hack monitors (opens them up) such as zisworks, are in theory fully capable of jerry rigging a custom backlight/edgelight strobing controller to the existing edgelights of many computer monitors, but this is really advanced user stuff. However, if you have some programming/microcontroller knowledge, and know your way around a soldering iron, you can probably do it -- once you've understood how monitor refreshing works & how strobing works from various high speed videos (link1, link2)

While a simple concept to retrofit a monitor to use strobing-based motion blur reduction (or 'enhance' a strobed monitor to be able to do more strobing features) -- this is extremely difficult to execute especially if the LCD panel isn't fast enough to complete GtG in the blanking interval between refresh cycles.

A few people have already done something roughly similar to this, with some very interesting successful results (including a modified 60Hz monitor) albiet not as high-quality as a true LightBoost monitor. However, an already-strobed panel may be even further improveable by adding extra options like shorter strobe lengths (lower/shorter persistence) or adding strobing to otherwise unsupported refresh rates (e.g. 72Hz) or new abilities such as strobing during variable-refresh-rate operation (which will have lots of flicker side effects that needs compensating, such as the info at this link).

Easiest modification considered as an "External Blur Reduction Adaptor":
There's no way to avoid hardware modifications. But for some models of monitors, they can be kept to a minimum (only for certain monitors). In theory, the simplest hardware hacking might be just two or three wires from the Arduino/microcontroller to the monitors' motherboard -- (1) one wire to a backlight flash trigger, and (2) one wire to a VSYNC timing signal. A program (patch/code) on the Ardunio/microcontroller would handle the rest. A small app on the PC side could configure settings whenever the Arduino is connected to the computer by USB cable; or it could be defined as constants in the microcontroller code; then no USB cable is needed.

OPTIONAL: (much harder) For even more advanced users is retrofitting a much brighter edgelight (via a thick edge bar, perhaps huge LEDs focussed through an edge-prism) to enable >1000+cd/m2 screen brightness, to permit usably bright <1ms ultralow-persistence strobing. Monitors that achieve 0.25ms persistence (e.g. PG278Q with the ULMB strobe length setting set to minimum length) are extremely dim at these settings, so another theoretical exercise is to invent an overkill replacement LED edgelight retrofit to enable even shorter persistence strobing -- for the maximum possible display motion blur elimination -- while still keeping usable brightness. This would be a modification I'd recommend to a high quality already-strobed panel...

IMPORTANT: If you decide to attempt this.... And you use microcontroller/Arduino signalling to control strobe on/offs.... Then make sure your strobe lengths don't vary -- a 1% variance (e.g. 10 microseconds in a 1 millsecond strobe flash per refresh cycle) creates a 1% variance in brightness -- creating candlelight flickering effects. Those microseconds MATTER a surprisingly LOT! 10 microseconds strobe length jitter/variances amplify human-visible flicker. Disable things like interrupts/communications during critical microcontroller routines, in order to keep strobe length as exact as possible. It's okay for strobe *phase* to jitter by microseconds unnoticeably -- but strobe *length* consistency is critical! And please use high quality electronics components & transistors/MOSFETs/etc to drive the strobing.
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