Edge lit lens
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Dinesh
Edge lit lens
This is an edge lens we made just today. The recon light is coming in from the left edge and the focused spot can be seen below the glass on the paper underneath. There is pretty severe aberration, partly because we use a line of light as ref and a spot source (the led) as a recon.No idea what the theory of aberrations would be for an edge lit HOE, since I've not seen one yet.
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- edgelit HOE.jpg (43.6 KiB) Viewed 4268 times
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Jeffrey Weil
Edge lit lens
Very cool Dinesh. A most exotic optic.
Jeff
I've never heard of one. Have you thought about figuring it out and writing up a paper? That would be a pretty meaty subject for a technically based conference.Dinesh wrote:No idea what the theory of aberrations would be for an edge lit HOE, since I've not seen one yet.
Jeff
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Dinesh
Edge lit lens
Thanks.Jeffrey Weil wrote:Very cool Dinesh. A most exotic optic.
Actually I have Jeff. But, believe it or not, the mathematics is pretty complex (never thought I'd hear myself say that!). I'm pretty deep in the study of holographic aberrations because I've had several projects lately where aberrations played a major part. It seems that a major problem with HOEs used in non-laser (or quasi laser) applications are the aberrations and most of the papers on holographic aberrations deal with aberrated coherent light, not partially coherent light.Jeffrey Weil wrote:I've never heard of one. Have you thought about figuring it out and writing up a paper? That would be a pretty meaty subject for a technically based conference.Dinesh wrote:No idea what the theory of aberrations would be for an edge lit HOE, since I've not seen one yet.
Jeff
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kyodai
Edge lit lens
Amazing! I did not think that was possible. For me as a beginner it looks like you're literally bending the physics of light. WOuld love to see it "in action", the picture came out a bit blurry (I guess good scientists and holographers arent necessary also good photographers...) but i can see where this is going. Excellent research here I'd say! Hail to the pioneers. Can't wait to see some holograms with this. =)
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Jeffrey Weil
Edge lit lens
Hello Kyodai,
Look what a normal edge lit display hologram is doing. It's also focusing light just like Dinesh's hoe but in a more complex fashion.
I would guess Dinesh intentionally made this hologram's image very simple compared to a full 3d display hologram with its many many "focal points" just so he could study the aberrations of an edge lit hologram without all the complexity of a 3d model and other artifacts getting in the way of seeing the pure influence on focused images by edge lit emulsions.
This is probably his "model" to study and apply that info to more complex images later. Classic basic research and classic Dinesh!
Or, he's been hired by a client to create a fancy optic and this is his solution
Jeff W
Look what a normal edge lit display hologram is doing. It's also focusing light just like Dinesh's hoe but in a more complex fashion.
I would guess Dinesh intentionally made this hologram's image very simple compared to a full 3d display hologram with its many many "focal points" just so he could study the aberrations of an edge lit hologram without all the complexity of a 3d model and other artifacts getting in the way of seeing the pure influence on focused images by edge lit emulsions.
This is probably his "model" to study and apply that info to more complex images later. Classic basic research and classic Dinesh!
Or, he's been hired by a client to create a fancy optic and this is his solution
Jeff W
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Dinesh
Edge lit lens
Jeff
Yes, it is a way of simplifying the process to understand what exactly is going on. I'm curious what an edge lit actually is. Is an edge lit hologram narrow-band, as in a volume hologram with Bragg planes? Are there Bragg planes in an edge lit? Is it a surface hologram as in resist? In this case there would be no selectivity and there'd be large dispersion. A single focused point of light reconstructed with a a broad band source, ie not a laser, would show dispersion. This one doesn't. I believe we need a new theory for edge lit because neither Kogelnik nor Fresnel zone plates cover this kind of hologram. It's a surface hologram that seems to have Bragg selectivity from a surface only a few microns thick, but smooth - none of the ridges that form on a resist.
Of course, it's also curiosity. It's a case of boldly stumbling where no man wants to go!
Yes, it is a way of simplifying the process to understand what exactly is going on. I'm curious what an edge lit actually is. Is an edge lit hologram narrow-band, as in a volume hologram with Bragg planes? Are there Bragg planes in an edge lit? Is it a surface hologram as in resist? In this case there would be no selectivity and there'd be large dispersion. A single focused point of light reconstructed with a a broad band source, ie not a laser, would show dispersion. This one doesn't. I believe we need a new theory for edge lit because neither Kogelnik nor Fresnel zone plates cover this kind of hologram. It's a surface hologram that seems to have Bragg selectivity from a surface only a few microns thick, but smooth - none of the ridges that form on a resist.
Of course, it's also curiosity. It's a case of boldly stumbling where no man wants to go!
I can't comment on this. There are Men in Black sitting in an unmarked black SUV across the road even now watching this house.....Jeffrey Weil wrote:Or, he's been hired by a client to create a fancy optic and this is his solution