Hi Aleksey,
I am not sure about this, but in my investigations, it appears that the Xenon HID Projector beam headlamps are only running at 35 Watts. Also they are very blue, which might not be good for colour rendering.
What I do know, is that unless you find a really cool source, they seem to cost more than the standard MH projector bulbs for commercial projectors - I have not seen a complete assembly for less than $350.
I was experimenting with some cheap halogen pod ones because they are small, cheap, and have an exit beam diameter of about 1.5". Oh, and did I mention that they were cheap???
If you know a source of the Xenon projectors, please let me know 'cos I want some blue eyes for my pet motorbike...
The big thing for me here is not the specific use of car headlamps themselves, it is the possibility that we can merge two separate beams from different fixtures into one single beam, without losing the quality of focus that comes from a small bulb in a well focussed assembly.
Also, for experimentation purposes, the lower colour temperature of halogens does not matter too much in my case, because my eyes seem to auto-adjust very easily to the colour balance of these bulbs. (My room lighting uses halogens, and my walls are cream. Before I stuck the shower curtain up, I was projecting onto a cream wall without too much discomfort...)
There are, actually, "ultra-white" car headlamp bulbs available, though, and some claim to be brighter than normal - check out the PIAA offerings. But, even if the light output per bulb is actually reduced, if we can feed an array of these things into one single beam, then it might not matter as much.
The main reason I am leaning in this direction is that it seems SO difficult to utilize all the light from the big 400 Watt bulbs without resorting to a massive reflector. I am just guessing, but if we could make use of maybe 80%-90% of the output of a lower powered light source, could we still get a brighter image than most people are getting from the big MH bulbs?
I don't know, and if someone can hit us with cheap, small, powerful HID bulbs that could be focussed with a small precision reflector into a well collimated beam, I would definitely follow that path instead!!!
All good fun!!!
Bill.
I am not sure about this, but in my investigations, it appears that the Xenon HID Projector beam headlamps are only running at 35 Watts. Also they are very blue, which might not be good for colour rendering.
What I do know, is that unless you find a really cool source, they seem to cost more than the standard MH projector bulbs for commercial projectors - I have not seen a complete assembly for less than $350.
I was experimenting with some cheap halogen pod ones because they are small, cheap, and have an exit beam diameter of about 1.5". Oh, and did I mention that they were cheap???
If you know a source of the Xenon projectors, please let me know 'cos I want some blue eyes for my pet motorbike...
The big thing for me here is not the specific use of car headlamps themselves, it is the possibility that we can merge two separate beams from different fixtures into one single beam, without losing the quality of focus that comes from a small bulb in a well focussed assembly.
Also, for experimentation purposes, the lower colour temperature of halogens does not matter too much in my case, because my eyes seem to auto-adjust very easily to the colour balance of these bulbs. (My room lighting uses halogens, and my walls are cream. Before I stuck the shower curtain up, I was projecting onto a cream wall without too much discomfort...)
There are, actually, "ultra-white" car headlamp bulbs available, though, and some claim to be brighter than normal - check out the PIAA offerings. But, even if the light output per bulb is actually reduced, if we can feed an array of these things into one single beam, then it might not matter as much.
The main reason I am leaning in this direction is that it seems SO difficult to utilize all the light from the big 400 Watt bulbs without resorting to a massive reflector. I am just guessing, but if we could make use of maybe 80%-90% of the output of a lower powered light source, could we still get a brighter image than most people are getting from the big MH bulbs?
I don't know, and if someone can hit us with cheap, small, powerful HID bulbs that could be focussed with a small precision reflector into a well collimated beam, I would definitely follow that path instead!!!
All good fun!!!
Bill.
Hi Xblocker,
You make an interesting point about the dates these MLA layers began to be introduced. I must do more research, and get my microscope out!
In my experience, though, I have been playing with a number of panels of the RGB OHP type, mostly being originally manufactured by Sharp, and having manufacture dates from '92 to '97.
The non-TFT ones in the old monochrome panels are nice simple optical filters: you can hold the panel up in front of an image you are viewing (e.g. a computer screen), and not see any distortion.
For four out of five of the TFT panels I have played with, if I hold them up in front of an image, then I get some serious distortion. The distortion gets worse as the angle increases (panel gets tilted), and seems to be in some part due to the shutters acting as a diffraction grating.
However, even directly holding the screen up with the light passing through perpendicular to the surface, there is significant image disruption. The image is recognisable, and not completely obliterated, but "something" is definitely interfering with the light as it flows through the panel - creating a much more diffuse output.
I had believed that the MLAs were introduced into LCD panel manufacture in order to bring the TFT devices into the mainstream - they have always suffered from having much less shutter area than the STN types (because the transistors on the panel took up a large surface area), and they were originally very directional. They needed (and most still do) a much brighter light source than the STN types to be usable. My understanding was that the MLAs were introduced to panel manufacture to reduce the demands on the light source - funneling more light through the small apeture, and as a side effect of their design, increasing the viewing angle of the light coming out of the front.
I could well be wrong on all this. But, the fact still remains that in many of the panels I have played with, there was and is this image disruption effect - ranging from mild diffusion to full scale ghosting and total loss of focus. (No, it's not the vodka - honest!!!)
If it is not MLAs, then why are the TFT screens not as good optical filters as the STN devices?
These panels themselves seem fully functional in use, and work quite well as a projection panel - except that they are interfering, to some extent, with the operation of the fresnels between the panel and the light source, which would send the light to the objective. Light does get scattered, and while an image (often quite cool) gets projected, it bothers me that there is a potential loss of contrast and brightness to this phenomenon.
Looking for enlightenment,
Bill.
You make an interesting point about the dates these MLA layers began to be introduced. I must do more research, and get my microscope out!
In my experience, though, I have been playing with a number of panels of the RGB OHP type, mostly being originally manufactured by Sharp, and having manufacture dates from '92 to '97.
The non-TFT ones in the old monochrome panels are nice simple optical filters: you can hold the panel up in front of an image you are viewing (e.g. a computer screen), and not see any distortion.
For four out of five of the TFT panels I have played with, if I hold them up in front of an image, then I get some serious distortion. The distortion gets worse as the angle increases (panel gets tilted), and seems to be in some part due to the shutters acting as a diffraction grating.
However, even directly holding the screen up with the light passing through perpendicular to the surface, there is significant image disruption. The image is recognisable, and not completely obliterated, but "something" is definitely interfering with the light as it flows through the panel - creating a much more diffuse output.
I had believed that the MLAs were introduced into LCD panel manufacture in order to bring the TFT devices into the mainstream - they have always suffered from having much less shutter area than the STN types (because the transistors on the panel took up a large surface area), and they were originally very directional. They needed (and most still do) a much brighter light source than the STN types to be usable. My understanding was that the MLAs were introduced to panel manufacture to reduce the demands on the light source - funneling more light through the small apeture, and as a side effect of their design, increasing the viewing angle of the light coming out of the front.
I could well be wrong on all this. But, the fact still remains that in many of the panels I have played with, there was and is this image disruption effect - ranging from mild diffusion to full scale ghosting and total loss of focus. (No, it's not the vodka - honest!!!)
If it is not MLAs, then why are the TFT screens not as good optical filters as the STN devices?
These panels themselves seem fully functional in use, and work quite well as a projection panel - except that they are interfering, to some extent, with the operation of the fresnels between the panel and the light source, which would send the light to the objective. Light does get scattered, and while an image (often quite cool) gets projected, it bothers me that there is a potential loss of contrast and brightness to this phenomenon.
Looking for enlightenment,
Bill.
Hi Invictum,
I don't know much about the outputs of modern computer power supplies - I am a few years out of date, unfortunately.
For my experimentation, I have been using a car batery charger to drive the bulbs. It probably has too high a voltage, and will shorten bulb life, but the bulbs I'm using are cheap, and easy to replace untill I get things right.
If anybody is playing with this stuff, check out the reflectors, bulbs, and any lensing setups. Quite often car headlamp fixtures have opaque panels inserted to shape the beam so that oncoming motorists don't get blinded...
The same can be said for the bulbs - some are designed to only send light in one direction. If you play with these, make sure you are using your full output capabilities!
Bill.
I don't know much about the outputs of modern computer power supplies - I am a few years out of date, unfortunately.
For my experimentation, I have been using a car batery charger to drive the bulbs. It probably has too high a voltage, and will shorten bulb life, but the bulbs I'm using are cheap, and easy to replace untill I get things right.
If anybody is playing with this stuff, check out the reflectors, bulbs, and any lensing setups. Quite often car headlamp fixtures have opaque panels inserted to shape the beam so that oncoming motorists don't get blinded...
The same can be said for the bulbs - some are designed to only send light in one direction. If you play with these, make sure you are using your full output capabilities!
Bill.
Lights and screens
Aleksey,
Rear screen projection screens are usually expensive. I haven't seen any material that is specifically made for that. And all the info that I have seen on them shows that the entire back of the screen is a frensal lens focused to a certain distance to increase brightness and the front is covered in micro lenses to increase viewing angle. If you can find one, you might try the screen from a rear projection t.v.
Undream,
The other day one of the bulbs in my proxima projector burned out ( don't worry, it has two ) When I pulled the bulb out I found that it is integrated with a reflector. The interesting thing is that the reflector is a "color correction filter" it only reflects about 70% of the light that hits it. The bulb itself has a large coil that is tightly packed. IT IS NOT A POINT SOURCE! which really supprised me. Another thing about the reflector is that it is not smooth. It is a bunch of small rectangle reflectors that make a virtual eliptical reflector. and the bulb is not really powerful. it is 430w 82v.
What I am trying to say is, The cut mirror reflector is probably the way to go. If that is the way the big boys do it we might want to try it too.
Joe
Aleksey,
Rear screen projection screens are usually expensive. I haven't seen any material that is specifically made for that. And all the info that I have seen on them shows that the entire back of the screen is a frensal lens focused to a certain distance to increase brightness and the front is covered in micro lenses to increase viewing angle. If you can find one, you might try the screen from a rear projection t.v.
Undream,
The other day one of the bulbs in my proxima projector burned out ( don't worry, it has two
) When I pulled the bulb out I found that it is integrated with a reflector. The interesting thing is that the reflector is a "color correction filter" it only reflects about 70% of the light that hits it. The bulb itself has a large coil that is tightly packed. IT IS NOT A POINT SOURCE! which really supprised me. Another thing about the reflector is that it is not smooth. It is a bunch of small rectangle reflectors that make a virtual eliptical reflector. and the bulb is not really powerful. it is 430w 82v.What I am trying to say is, The cut mirror reflector is probably the way to go. If that is the way the big boys do it we might want to try it too.
Joe
Woneill
Lack of efficiency in lighting is a real problem not easy to solve for DIY people.
For a start you loose 50 percent light because projection panels work with polarised light. Half the light we supply is wasted.
Modern manuifacturers use polarising recyclers by prisms and wave retarders so can utilise much more light than we can.
Also we use lights that do not have sharp point source so reflector efficiency not so high as manufactured items.
Some of our reflectors are not optimum.
In addition 3 panel manufacturers use polysilicon panels which have greater transmissivity. than projection panels.
3 panel manufacturers use MLA (micro lens array) to direct light parallel through panel which further increases light throughput and increases contrast by reducing stray light.
What can we do. Short of spending a lot of money on polarising recyclers and buying a sheet of MLA and buying a point source bulb and matching reflector, probably nothing.
People do what they can with whats available at good prices and some results are pretty darn good. But I take your point. Without investigation we get to a certain level and then stop.
Maybe we could find out how to use the half of the light that is wasted. Thats a big gain for a start. So we have firstly get it going, then improvements if economic and possible.
Lack of efficiency in lighting is a real problem not easy to solve for DIY people.
For a start you loose 50 percent light because projection panels work with polarised light. Half the light we supply is wasted.
Modern manuifacturers use polarising recyclers by prisms and wave retarders so can utilise much more light than we can.
Also we use lights that do not have sharp point source so reflector efficiency not so high as manufactured items.
Some of our reflectors are not optimum.
In addition 3 panel manufacturers use polysilicon panels which have greater transmissivity. than projection panels.
3 panel manufacturers use MLA (micro lens array) to direct light parallel through panel which further increases light throughput and increases contrast by reducing stray light.
What can we do. Short of spending a lot of money on polarising recyclers and buying a sheet of MLA and buying a point source bulb and matching reflector, probably nothing.
People do what they can with whats available at good prices and some results are pretty darn good. But I take your point. Without investigation we get to a certain level and then stop.
Maybe we could find out how to use the half of the light that is wasted. Thats a big gain for a start. So we have firstly get it going, then improvements if economic and possible.
ap0the0sis:
I dont have the perfect light source, I was just trying to help you with your suggestion, by all means go ahead and try those, but I don't think you will have much to be happy with afterward.....there is ~3inches of fillament in those to do the 300 or 500, etc watts, the light is distributed too much.
The best light source most likely like in the first set of posts says, is Metal Halide (MH) Ushio actually has some really cool MH assemblies of lower wattage ~150-250 watt that i want to get more info on, I think that they have some serious potential, but back to your bulbs.....you might get a decent effect out of them if you encase them in an old elipsoidal stage light....still not as good as metal halide, but it would work and would focus the light as much as possible
I dont have the perfect light source, I was just trying to help you with your suggestion, by all means go ahead and try those, but I don't think you will have much to be happy with afterward.....there is ~3inches of fillament in those to do the 300 or 500, etc watts, the light is distributed too much.
The best light source most likely like in the first set of posts says, is Metal Halide (MH) Ushio actually has some really cool MH assemblies of lower wattage ~150-250 watt that i want to get more info on, I think that they have some serious potential, but back to your bulbs.....you might get a decent effect out of them if you encase them in an old elipsoidal stage light....still not as good as metal halide, but it would work and would focus the light as much as possible
its been a while since i've done any projector work. but we did reclaim our cloth and still hope to build a screen sometime. really, we like our setup as is for the moment and we just enjoy watching movies, playing nintendo 64, and bigscreen soccer games.
funny thing is, ive never watched soccer in my life, but something about watching it 8 foot wide makes it exciting!
anyway, no new info, but i'd still like you guys to submit your results at our site. i think a list of 15 or 20 submissions with good results would be a good collection of information.
Submit you projector details here
funny thing is, ive never watched soccer in my life, but something about watching it 8 foot wide makes it exciting!
anyway, no new info, but i'd still like you guys to submit your results at our site. i think a list of 15 or 20 submissions with good results would be a good collection of information.
Submit you projector details here
Will do Zoboo, as soon as I get a projector, and a panel, and a screen, and a...
I'm not so sure I should go with headlights now. For one, I'm pretty sure that one wouldn't be strong enough, and if the power supply can only power one, it's not really worth it. Even if it could power both, I'd need something to combine the lights etc.
I might screw around with it later today anyway though.
I'm not so sure I should go with headlights now. For one, I'm pretty sure that one wouldn't be strong enough, and if the power supply can only power one, it's not really worth it. Even if it could power both, I'd need something to combine the lights etc.
I might screw around with it later today anyway though.
Hey,
I have a suggestion.
Maybe good information could be gathered if someone goes to the patent division in a local library and looks up, “projector,” technology. The details should have parts, measurements, scientific data etc., that we could use with the DIY project. It might be a good step forward. If somebody is willing [I don’t have the time now {soon}], that would be great.
Also a link for an LCD list: http://www.commspecial.com/resolutions.htm
I have a suggestion.
Maybe good information could be gathered if someone goes to the patent division in a local library and looks up, “projector,” technology. The details should have parts, measurements, scientific data etc., that we could use with the DIY project. It might be a good step forward. If somebody is willing [I don’t have the time now {soon}], that would be great.
Also a link for an LCD list: http://www.commspecial.com/resolutions.htm
eebasist said:
That's close to what I'm looking into. After seeing this product:
http://www.premier-lighting.com/tipa/tipa.html
I ordered a reflector and lens from an 8" fresnel stage light from Secoa and intend to experiment away. Not having specific data on the reflector, my fear is that the light source of my big honking 400w MH bulb won't be able to fit anywhere near the focal point. From what I've seen so far, stage lighting fixtures use very small high power bulbs which can fit deeply into a reflector. We'll see once I get it.
I tried to pick up a reflector like marklar's. Cooper makes the Portolio line and sells though Home Depot, so I called them with the model - H7684T. The quote was $181.56 plus $25.58 for the trim ring plus shipping. Youch! Well beyond what I wanted to spend on a reflector!
So, tech head and undream may have the practical answer. What sort of adhesive do we use to allow fairly precise tweaking and aiming of little mirrors inside a form which won't care about heat? Someone a while back had suggested using one of those laser pointers for checking focal points, and that might really help in aligning them in this case.
I ran into the same problem with Marklar's projector. It was just too expensive.......so i decided the ellipsoidal stage light would be better.....the thing is, with a quartz halogen bulb it could be very good, they are desined to use a relativly large bulb fillament. But i probably wont go that route yet since i've got two working projectors and that only need light sources....time to modify stuff
BTW guys i work in a tech transfer office and have access to many differrent patent search tools.
BTW guys i work in a tech transfer office and have access to many differrent patent search tools.
look at my calculations....
wait a minute, the thing in the middle is where the image that is to be projected is placed, right? but the size of this thing seems to be too small to fit a projection panel....are we still going to use a panel.
and, if we use a panel, then to illuminate it's 10.4" we use say 575W metal halide bulb. but if we use a smaller screen, look at this:
10.4 / 49000 = 5.6 / x where the x is the numberof lumens and the first numbers are the diagonals
in this case we will need about 22000 lumenswhich we can easily get from a variety of CHEAP bulbs.
MY POINT IS>>> do we want to use the projection panel and have to use very powerfull and big bulbs? if at the same time we could use a small bulb on a small LCD...
aleksey
mycamel said:
wait a minute, the thing in the middle is where the image that is to be projected is placed, right? but the size of this thing seems to be too small to fit a projection panel....are we still going to use a panel.
and, if we use a panel, then to illuminate it's 10.4" we use say 575W metal halide bulb. but if we use a smaller screen, look at this:
10.4 / 49000 = 5.6 / x where the x is the numberof lumens and the first numbers are the diagonals
in this case we will need about 22000 lumenswhich we can easily get from a variety of CHEAP bulbs.
MY POINT IS>>> do we want to use the projection panel and have to use very powerfull and big bulbs? if at the same time we could use a small bulb on a small LCD...
aleksey
Aleksey,
If my memory serves, the calculation you propose should be based on area and not on the screen/image diagonal.
Unfortunately, even doing it that way, it still only translates to the projected image if it is the same size of the panel...
Whether you use a 10.4" panel, a 5.6" panel, or a 1.8" panel: if they are each used to project a 100" image at the same brightness, then the total light flux pasing THROUGH each panel will be equal. (The original light source energy needed to achieve this throughput is dependent on the efficiency of the panel.)
It is the size of the image, and how thinly spread the light energy is over its area that is the final determinator in the required output brightness of the projector...
The flashy new little devices with thousands of ANSI lumens are intended to project big images in big bright auditoriums. To achieve the same brightness in a 4' image on your bedroom wall, you will probably need only a couple of hundred lumens.
The reason for using a bigger panel is cheapness/availability, and the possibility that in the bigger panels, the LCD shutter area is bigger with respect to the TFT transistor area, than it is in the smaller panels. (The LCD shutters compete for space on the panel surface with the TFT transistors which are mounted directly on the silicon surface.) If this increased area ratio is the case, then the bigger panels would be more efficient. Unfortunately, their size introduces other problems as we all know...
Bill.
If my memory serves, the calculation you propose should be based on area and not on the screen/image diagonal.
Unfortunately, even doing it that way, it still only translates to the projected image if it is the same size of the panel...
Whether you use a 10.4" panel, a 5.6" panel, or a 1.8" panel: if they are each used to project a 100" image at the same brightness, then the total light flux pasing THROUGH each panel will be equal. (The original light source energy needed to achieve this throughput is dependent on the efficiency of the panel.)
It is the size of the image, and how thinly spread the light energy is over its area that is the final determinator in the required output brightness of the projector...
The flashy new little devices with thousands of ANSI lumens are intended to project big images in big bright auditoriums. To achieve the same brightness in a 4' image on your bedroom wall, you will probably need only a couple of hundred lumens.
The reason for using a bigger panel is cheapness/availability, and the possibility that in the bigger panels, the LCD shutter area is bigger with respect to the TFT transistor area, than it is in the smaller panels. (The LCD shutters compete for space on the panel surface with the TFT transistors which are mounted directly on the silicon surface.) If this increased area ratio is the case, then the bigger panels would be more efficient. Unfortunately, their size introduces other problems as we all know...
Bill.
headlights
When i mentioned headlights in my post, i was'nt thinking of using
the headlight bulb, they are just not bright enough
Im just saying use the reflector
on my car i have two fog lamps on the front spoiler,they are about
6"+4", if you were to get somthing like that and just use the
reflector part, adapt it to take one of those high power capsule bulbs, you end up with somthing like whats in an overhead
When i mentioned headlights in my post, i was'nt thinking of using
the headlight bulb, they are just not bright enough
Im just saying use the reflector
on my car i have two fog lamps on the front spoiler,they are about
6"+4", if you were to get somthing like that and just use the
reflector part, adapt it to take one of those high power capsule bulbs, you end up with somthing like whats in an overhead
Xenon Light
May be of interest! Here's a pic from 10" single panel projector light unit. Projectors name is 'GP Movin 2001". It's a 4-pack xenon unit with 4x35 Watts. It should last up to 6000h and costs about 76 EUR. Xenon lamps dont produce so much heat and can work with smaller, more silent fans. If somebody is interested:
http://www.gp-elektronik.de
May be of interest! Here's a pic from 10" single panel projector light unit. Projectors name is 'GP Movin 2001". It's a 4-pack xenon unit with 4x35 Watts. It should last up to 6000h and costs about 76 EUR. Xenon lamps dont produce so much heat and can work with smaller, more silent fans. If somebody is interested:
http://www.gp-elektronik.de
Attachments
Re: Xenon Light
Cool! I'd never even considered an ARRAY of smaller lights and reflectors! This would help keep the light rays going straight through the LCD apertures. They sort of look like light headlight reflectors, don't they? I'd guess they must use a large high quality fresnel after the panel to make this work. Anyone understand enough German (or whatever it is) to know if its mentioned on the site?
xblocker said:
Cool! I'd never even considered an ARRAY of smaller lights and reflectors! This would help keep the light rays going straight through the LCD apertures. They sort of look like light headlight reflectors, don't they? I'd guess they must use a large high quality fresnel after the panel to make this work. Anyone understand enough German (or whatever it is) to know if its mentioned on the site?
Re: Re: Xenon Light
youd need the fresnal in front of (before) the lcd. so that the rays are paralell, thats the point of parabolic reflectors. scratch that as long as all four reflectors are parabolic it might work??????? someone let me know please!!!!!!!!
anyway here's a site for metal halide bulbs
home depot dont have ballests
i dont know how much you guys are paying but i've heard/read prices hier than this
sorry bout the spelling im on a wave key board its confusing im a pecker
mycamel said:
youd need the fresnal in front of (before) the lcd. so that the rays are paralell, thats the point of parabolic reflectors. scratch that as long as all four reflectors are parabolic it might work??????? someone let me know please!!!!!!!!
anyway here's a site for metal halide bulbs
home depot dont have ballests
i dont know how much you guys are paying but i've heard/read prices hier than this
sorry bout the spelling im on a wave key board its confusing im a pecker
Hey, I just noticed this bulb at bulbs.com:
http://www.bulbs.com/products/product_detail.asp?page=products&inventory=9722
Now I know this thing is expensive, but otherwise it seems perfect. The color temp. is good, it lets out 60K lumens, it's only 175 watts, it lasts 7.5k hours, it's not too big, and best of all, the reflector is built onto it. Is this a great bulb, or am I missing something here?
http://www.bulbs.com/products/product_detail.asp?page=products&inventory=9722
Now I know this thing is expensive, but otherwise it seems perfect. The color temp. is good, it lets out 60K lumens, it's only 175 watts, it lasts 7.5k hours, it's not too big, and best of all, the reflector is built onto it. Is this a great bulb, or am I missing something here?
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