Blur Busters Forums

RLBURNSIDE wrote:*snip*

This is all a non-issue if you could somehow pack lasers in a display
Doesn't have to be a projector for this tech to catch on it could be used on TV's/Computer Monitors

If anything flicker is more of an issue since most people can't stand it and most of them run their TV's at a lowly 60hz so they're bound to see a lot of flicker and complain

spacediver wrote:this thread is win

RLBURNSIDE wrote: That's why you see 5mw lasers in these pocket projectors, otherwise Sony would get sued to smithereens the second some kid blinded himself by staring into it.

Actually each laser outputs about 150mw EACH! Over 300mW! Microvision gets around this with fuzzy math and a cozy relationship with regulators.

RLBURNSIDE wrote:
Lawsuits and damages could be in the millions. Financial backers would be aware of this. One of the first things a lawyer would ask is : "what's the chance of someone damaging their vision from this?". You could say zero but they would likely need independently verified scientific proof, to limit liability exposure.

Certification is the responsibility of the manufacturer or the importer (In this case Sony or Microvision.) The FDA cannot place this burden on distributors of the monitor. The projectors already passed certification before ending up in my product.


You also brought up some great scary ass points about the legal side of things RLBURNSIDE.



--------Begin Professional Legal Disclaimer -------
I am NOT a company.

---------End Professional Legal disclaimer---------

thatoneguy wrote: This is all a non-issue if you could somehow pack lasers in a display
Doesn't have to be a projector for this tech to catch on it could be used on TV's/Computer Monitors

Agreed! My screen stops all laser light so there is no danger to the eyes at all in terms of coherence.
My monitor has a big layer of Gorilla Glass 4 to prevent breakage of the screen in case the screen drops or is hit as well as other safety measures to prevent direct exposure to the lasers in case of any kind of failure.
Also my monitor has "redundant back up safety features".

-Update-
Optical Hardware Specifications of my prototype laser monitor so far:

1st modified Sony laser projector: Different wavelength laser diodes are put in for increased gamut
Red: 638nm & 639nm diodes
Green: 532nm & 530nm diodes
Blue: 442nm (1 diode)

2nd Modified Sony laser projector: Specific Neutral Density filters are placed over the light sensors so that both projectors are 'tricked' into increasing the brightness of all lasers
Red: 642nm (2 each)
Green: 522nm (2 each)
Blue: 450nm (1 diode)

---Combined with----

A special Polymer Film Retarder & Polarized Beam Spliter Cube to combine both projectors for increased brightness & color gamut, reduction of scan line 'hopping' artifacts.

Projected onto screen layers:

Layer 1.) A one sided Non depolarizing low iron acid etched glass sheet with my proprietary water clear despeckle film bonded to the etched side facing away from the projectors. (Back projected polarization preserving 3D Plate)

Layer 2.) A big sheet of Gorilla Glass 4 with a layer of high contrast film bonded to its surface facing towards the projectors (Middle Plate, safety layer, beam alignment)

Layer 3.) Unique Anti Reflective Glass (98% light transmissible with NO color cast , NO reflections) (Front screen, surface Plate)

All 3 layers optically bonded together to comprise my monitor screen



----Internal hardware solutions are built into the monitor for no hassle plug n play 3d content.----
1080p@60H 3D
Frame packing (FP) 3D Blue Ray format is converted in the monitor to a passive polarized setup.


More updates to come...

Light23 wrote:
2nd Modified Sony laser projector: Specific Neutral Density filters are placed over the light sensors so that both projectors are 'tricked' into increasing the brightness of all lasers

heh, nice idea

holy crap this thread is still going

Light23 wrote:NO reflections)

yes there are reflections, just much less than from plain glass

btw for layer2, you may be interested in trying a circular polarizer instead of whatever "contrast film" you have right now
https://technology.ihs.com/509943/why-a ... -polarizer

hows the ansi contrast of the whole thing?

flood wrote: hows the ansi contrast of the whole thing?

My monitor uses 10 laser beams to generate “pixel pulses” that "paint" each pixel individually (zero pixel gap), black pixels are made by simply turning off all ten lasers. Therefore, it essentially has infinite contrast ratio (specs state >5000:1 ,10,000:1 and 80000:1).
Competing LCD tech creates a black pixel by dumping the light as waste heat. Not only does this consume more energy, the blacks produced are not tru black, but a shade of gray.

There are scattering losses in the plastic Correction exit Lens used on the Sony and Celluon projectors.
I removed the plastic lens window on the Sony projector. This gave me a slight bowtie image exactly like the showwx+. (The lens compensates for the slight bowtie image.)

By removing the plastic window I got a sharper image with blacks that equal the showwx+.
The Showwx+ never had a plastic lens, only a A.R. glass window.

(This significant corrective lens was also the source of chroma aberrations and contrast problems in the final image that plagued the Sony and Celluon projectors but not the Showwx+.)

flood wrote:

Light23 wrote:NO reflections)

yes there are reflections, just much less than from plain glass

No, I mean NO reflections at all. The front plate reduces reflections to less than 1% using a proprietary manufacturing process called magnetron sputtering.
(Magnetron sputtered thin film multi-layered anti-reflection coating)


The technology deposits precisely controlled layers of highly energized metal oxides onto an Extra Clear lower iron glass substrate.

It provides the highest brightness and contrast levels available, Reflection-free viewing and is 70% UV protected to preserve the other screen materials from damage throughout the lifetime of the monitor.

Its like no glass at all. (My glass is on the left)

flood wrote:btw for layer2, you may be interested in trying a circular polarizer

I can't use a circular polarizer for my back projected passive setup. Thats why my first layer is a Non depolarizing screen made of acid etched low iron float glass to preserve polarity.

spacediver wrote:

Light23 wrote:
2nd Modified Sony laser projector: Specific Neutral Density filters are placed over the light sensors so that both projectors are 'tricked' into increasing the brightness of all lasers

heh, nice idea

Therefore, it essentially has infinite contrast ratio

i'm asking for measurements of ansi contrast.
you can turn off the laser obviously, but light that gets back-scattered from other lit parts of the screen will reflect off whatever enclosure you use and increase the black level.

I mean NO reflections at all. The front plate reduces reflections to less than 1%

i know quite well how ar surfaces work. and 0.5% is different from 0%.

about polarizer: the fact that the laser light is polarized doesn't matter. the goal is to reduce diffuse reflections from underneath the stack. ~50% of the laser light will still shine through.

flood wrote: i know quite well how ar surfaces work. and 0.5% is different from 0%.

My apologies Flood, I merely meant to convey that this wasn't just a cheap matte 3M anti glare film that I was applying to the display. (My over explanation is directed more to others reading in the future attempting a similar project.)

flood wrote: light that gets back-scattered from other lit parts of the screen will reflect off whatever enclosure you use and increase the black level.

Well I was going to sandwich the screen between 2 pieces of the AR glass until I realized that the AR glass on the inside of the monitor was screwing up my non depolarizing screen because of the AR coatings angle of incidence.
The enclosure itself is lined with a black velvet like material to absorb any stray light.
The high gain/contrast screen is there to absorb small stray light from the front and back as well. (This also eliminates the whole 'blooming in the high contrast areas' problem.)

flood wrote:

about polarizer: the fact that the laser light is polarized doesn't matter. the goal is to reduce diffuse reflections from underneath the stack. ~50% of the laser light will still shine through.

Its a great idea but 50% light loss is unacceptable for my 3D laser monitor because of the lower lumen nature of the laser projectors & the light loss already factored in by my passive 3D setup.

------------------------------------------------------------------------------------------------------------------
(Edit: After doing some more research on the patents of this method and such, I think the idea is sound Flood. I think this will be the way to go for my 2d monitor (without the acid etched glass).
Thanks for the heads up on this method Flood.

thatoneguy wrote:

RLBURNSIDE wrote:*snip*

This is all a non-issue if you could somehow pack lasers in a display
Doesn't have to be a projector for this tech to catch on it could be used on TV's/Computer Monitors

If anything flicker is more of an issue since most people can't stand it and most of them run their TV's at a lowly 60hz so they're bound to see a lot of flicker and complain

Well, the title of this thread is "laser projectors general", although rear projection could be considered similar to a traditional TV or monitor.

I agree about low refresh rates and scanned displays, I used to hate 60hz flicker on CRTs and wouldn't even consider using one lower than 72hz, 85+ ideally.

But running at 120hz would be great for a raster display, since it's a common multiple of 24, 30, and 60, and would result in pretty low lag and latency, plus it's easy to simply repeat frames to maintain the cadence of the original material.

Even if you enjoy frame interpolation (like I do) on movies, if you had, say, a 72hz or 120hz display instead of a 60hz one, and was watching lowly 24p movies interpolated, then the quality of the interpolation would be better for the simple fact that there's no cadence mismatch and you only see 2/3 or 4/5 of the frames are interpolated, with 1/3 or 1/5 being the original. That said, you'd still have to reduce the motion blur quite significantly in the "key" frames. Super fast frame rate with blurry frames looks the same, just a slightly smoother blur. That's actually the purpose of motion blur caked into the frames of 24p movies, it's to mask the low framerate. As soon as you run a higher framerate you need to first de-blur, then interpolate the sharper keyframes. And deblurring is a tough problem. It can be done but not perfectly.

I don't think this project makes sense at computer monitor sizes, personally. Especially not when OLED PC monitors are out now and prices will inevitably come down.

spacediver wrote:

Light23 wrote:
2nd Modified Sony laser projector: Specific Neutral Density filters are placed over the light sensors so that both projectors are 'tricked' into increasing the brightness of all lasers

heh, nice idea

Indeed that's a clever hack.

It could be of immediate benefit to anyone who owns one of these pico projectors and is willing to do even the slightest bit of modding, plus ND2 / ND4s are really cheap.

Might want to read the breakdown from Karl Guttag about the Celluon / Sony pico projector:

http://www.kguttag.com/2015/07/13/cellu ... ical-path/

I was all interested in buying it to play around but the resolution is low, and it's because the inertia of their mirror forces them to scan back and forth and it gives a kind of wavey raster pattern instead of straight lines. The effective resolution suffers because of the way the image has to be resampled due to its bowtie scanning pattern.

I was also considering buying a Sony projector and replacing the lasers with more powerful ones, but I have to ask, why stop with just changing the wavelength of the lasers to expand the gamut? Or even using ND filters to short circuit their detectors?

Just use a step up transformer and higher powered lasers with the same output signal and you're done.

Also what I wrote before is wrong apparently. The green lasers in the Sony are probably at least 50mw according to Karl Guttag. And there is a 50% lumens loss (at least) due to all the de-speckling being done optically. I believe Light123's screen could result in a double of the lumens just by skipping the despeckling steps in the design. Of course then that begs the question, why start with the Sony or Celluon to begin with, they already "solve" the speckle issue internally. Lasers that are scanned i.e. not stationary have a different regulatory power limit than stationary ones, since the light is spread out it is less dangerous and therefore higher mw lasers are allowed in consumer grade devices (hence why 50mw green lasers are used in this projector legally and still achieve class 3R certification). Karl posted a link to the reasoning behind this in the comments of his article.

But the hack to improve the color gamut, or lumens, by either replacing the lasers or increasing the power going to the current ones indirectly through the ND filters is something which many enthusiasts / tinkerers could immediately benefit from.

I encourage you, Light123, to post picks of your homebrew laser hacks on these devices and share the results here. Personally I think your screen solving the speckle issue is solving an already more or less solved problem and loses out on one of the best benefits of this projector : a focus free image allows incredible placement flexibility. And also curved screens, like curved black screens for gaming with those projection mapping middlewares would be super cool, if the laser power were increased enough.

There are just a couple aspects of the design of these devices that I fundamentally don't like, such as the inability to resolve horizontal / vertical lines without blur. Of course those issues could be fixed by increasing the internal resolution to 2x 1080p but that is such a colossal waste of pixels. Call me old fashioned but horizontal lines in a raster scanner should be perfectly straight and fully resolved. This is a fundamental design limitation of the way they move their mirrors. They would have been better trying to achieve perfect 720p resolution instead of trying to fake 1080p and not even reaching 720p. That's right, these projectors are lower than 720p in terms of resolvable detail. Still very innovative and fun toys, but not (yet) serious competition for the low end projector market.

If you boost the laser power you could have a 100-120 inch low persistence display. Boost the gamut and it could reach DCI P3 and maybe even do HDR with the right tone mapping curve.

You could do that with some kind of variable transformer with a built in curve to convert from Rec 709 to PQ gamma. HDR decoding support needs to be done at the projector side, not at the PC side. Well, actually both. You would tunnel PQ gamma encoded video over an HDMI connection (it's just bits after all), but then you need to properly map those values to voltages inside the projector.

And then there's the issue of what kinds of bit depths are supported. I wonder what these pico devices look like with Deep Color (30 bit) and showing a banding test pattern:

http://www.bealecorner.org/red/test-pat ... -16bit.png

Can you tell us? The lasers are analog so the only limit there is the bit depth of the DACs they are using to drive them (and any other signal processing, plus limitations of HDMI input bandwidth. This is why, for example, you need to drop to 422 chroma to send 10- or 12-bit at 1080p / 60 over HDMI 1.3-1.4 devices like this one probably is). But we won't know until we test.

I suspect it's 8 bit all the way because otherwise they would announce support for 10-bit or 12-bit support, wouldn't they? They did some silly mistakes in the design of these projectors, like for example the charger not charging fast enough to use the projector continuously forever without running out of power, even while plugged in. Total facepalm that one. That is probably my biggest deal breaker for these projectors. Actually, even worse is you still can't even buy the Sony here in Canada, it's so absurd / annoying. I know, I know, that's like going to a restaurant and saying the food sucks and the portions were way too small.

But I'd like to do some laser hacking too. Let us know if you can pump up the lumens from the paltry / neigh worthless 32 lumens. I have a 2000 lumen projector and it's still not bright enough for my wall sized display. I suspect the biggest problems you'll run into are power supply issues and heat dissipation.

Just sticking an ND4 might overload the power circuits, so I'm curious how much you can boost the lumens using that hack.