I'm currently in the design stage of my 7" lilliput PJ but i'm stuck at which lens I need?
I'm going to use a 250w HQI Metal Halide as the light source
Anyone suggest any optic specs for me?
I'm going to use a 250w HQI Metal Halide as the light source
Anyone suggest any optic specs for me?
No replys?
Maybe I need to elaborate a bit more!
I am after obtaining an image size of no more than 100" (80" at best)
As mentioned before using a 250w source and a lilliput 7" LCD panel.
I am looking to buy a kit from lumenlab but all of their PJ's are made using larger LCd panels
Anyone out there point me in the right direction??
Maybe I need to elaborate a bit more!
I am after obtaining an image size of no more than 100" (80" at best)
As mentioned before using a 250w source and a lilliput 7" LCD panel.
I am looking to buy a kit from lumenlab but all of their PJ's are made using larger LCd panels
Anyone out there point me in the right direction??
It's not cheap!
Works out around £150 UKP all delivered
If anyone knows of a cheaper on then please elaborate!!
And if anyone wants to point me in the right direction on that lens kit then i'd be happy!
Works out around £150 UKP all delivered
If anyone knows of a cheaper on then please elaborate!!
And if anyone wants to point me in the right direction on that lens kit then i'd be happy!
well, as far as i know, in terms of high resolution and 16 by 9 ratio there is no other small lcd,
the next best thing is to get a 15 inch lcd monitor. now there are some 15.4inch 16 by 9 lcd monitors but not as easy to find as the regular 15.1 inch monitors.
the next best thing is to get a 15 inch lcd monitor. now there are some 15.4inch 16 by 9 lcd monitors but not as easy to find as the regular 15.1 inch monitors.
15 inch was an option but I need to keep this baby small!
Looks like 7" is the only way to fly!
Throw distance is going to be around 10 foot if that helps....
Looks like 7" is the only way to fly!
Throw distance is going to be around 10 foot if that helps....
you can use 6 to 8 foot throw with a 15 inch lcd as far as i know,
but it would only be 45 to 60 inch screen size
but that's all i want............
know if you want bigger, then ok, nevermind.
but it would only be 45 to 60 inch screen size
but that's all i want............
know if you want bigger, then ok, nevermind.
iv seen alot useing a 80mm triplet.... im useing a sharp ohp panel that is 10.5 inches diagnal and im useing the lense that came with my ohp a doublet ... and im throwing image 15 ft and getting 120 inch diagnal screen with very little screen door ... but i am just useing the wall .. not a screen.
Thanks for the info, i'm going to start pricing some up then!
With regards to fresnel lens, do I need two (Front & Back) or will one suffice?
I have seen a lot of peoples designs using two but some people seem to use one, enlighten me!
How do I work out how far my LCD needs to be to the lens? Or does it not matter?
With regards to fresnel lens, do I need two (Front & Back) or will one suffice?
I have seen a lot of peoples designs using two but some people seem to use one, enlighten me!
How do I work out how far my LCD needs to be to the lens? Or does it not matter?
everybody use 2 fresnels but some people use them unsplitted (mean stick together).
about the distance, if you have a long throw(more than 5m) the projection lens will be a distance from the lcd equal to the focal of the projection lens. If you have a shorter throw distance the lcd-lens distance will increase. just test the righ position to get a sharp image.
or calculate from 1/f=1/p +1/q
where
f is your projection lens focal
p is the lcd to projection lens distance
q the projection lens to screen distance.
q/p will give you the magnification of your system
size of your lcd times the magnification will give you the size of your projected image.
you are all set
about the distance, if you have a long throw(more than 5m) the projection lens will be a distance from the lcd equal to the focal of the projection lens. If you have a shorter throw distance the lcd-lens distance will increase. just test the righ position to get a sharp image.
or calculate from 1/f=1/p +1/q
where
f is your projection lens focal
p is the lcd to projection lens distance
q the projection lens to screen distance.
q/p will give you the magnification of your system
size of your lcd times the magnification will give you the size of your projected image.
you are all set
I am building a Lilliput 7" too and I have found that the kits at DIY Projector Company DIYPC Website are pretty good. In particular the PICO kit is failry small, this is what I am building, there is mixed feelings about the 135mm Triplet, but others seem to think that it is good for the 7" LCD's..😀
Right, time to get down to some slightly more techincal drawings than my last set!
Trying to get my head around some easy CAD software but its not going to well!
I'll post my plans up when i'm done so people can have alook and comment and improve (hopefully!)
Trying to get my head around some easy CAD software but its not going to well!
I'll post my plans up when i'm done so people can have alook and comment and improve (hopefully!)
What are the advantages of splitting the fresnel?
And by constructing a rotating tube to hold my lens, will this effectivley give me a focus ring?
And by constructing a rotating tube to hold my lens, will this effectivley give me a focus ring?
Seen as it's my day off i've gone into design mode! Below is my preliminary design, nothing is to scale but all the parts I think i need are there
Box is going to be constructed out of sheet metal, hopefully this will act as a huge heatsink and help out with the cooling
I've not included any cooling options on the plan as yet, i'm going to do that when all my measurments are good.
I am struggling to work out how far my LCD needs to be from my lens, according to my calculations it should be 7.85 inches away, am i right?
Does the distance between the light source and the mirror make any difference or can that be any length?
I'm trying to keep this PJ as small as possible so want all my measurments to be right from the beginning!
I need to know the following if someone could help......
Box is going to be constructed out of sheet metal, hopefully this will act as a huge heatsink and help out with the cooling
I've not included any cooling options on the plan as yet, i'm going to do that when all my measurments are good.
An externally hosted image should be here but it was not working when we last tested it.
I am struggling to work out how far my LCD needs to be from my lens, according to my calculations it should be 7.85 inches away, am i right?
Does the distance between the light source and the mirror make any difference or can that be any length?
I'm trying to keep this PJ as small as possible so want all my measurments to be right from the beginning!
I need to know the following if someone could help......
- Is my calculated distance between the lens and LCD correct (7.85 inches) 😕
- In theory, would the design shown above work ie; am I missing anything apart from cooling? 😕
- Status
- Not open for further replies.