This sounds very promising, but I am curious as to the amount of chromatic abberation that exists and how expensive will it be. Cassegrain telescopes (which the developers compare this technology to) can be significantly more expensive, however more compact, than traditional devices. “Folded mirror” lenses may become a significant niche market, but I don’t see professionals dumping their traditional telephoto lenses anytimes soon.
To reduce camera thickness but retain good light collection and high-resolution capabilities, Tremblay and colleagues replaced the traditional lens with a “folded” optical system that is based on an extension of conventional astronomical telescopes that employed mirrors, such as the Cassegrain telescope, which was developed in 1672.
“The folding idea was new in 1672, but they were doing it with two separate mirrors. We cut all of our reflective surfaces out of a single component and quadrupled the number of folds,” said Ford.
Instead of bending and focusing light as it passes through a series of separate mirrors and lenses, the new folded system bends and focuses light while it is reflected back and forth inside a single 5 millimeter thick optical crystal. The light is focused as if it were moving through a traditional lens system that is at least seven times thicker.
Another potential drawback is that this is only good for fixed-focus lenses at the present time, although the creators promise that adjustable folded optics are in the future. I think that those that care about optics are going to take a long hard look at this before making any commitments.
The Adult Swim Moonimites in Boston makes for a better optical related story…
…but I never watch their show…’cept for a couple of Robot Chicken Trekkie parodies…
// totally hijacked thread?
Hey, if they can get better weight – to – zooming ratio, there should be an increase in used telephoto sales on eBay from thousands of paparazzi’s.
Pure reflectors have no chromatic aberration, but this lens isn’t a pure reflector since it contains an optical crystal sandwiched between the mirrors. But since the crystal face is perpendicular to the light when it enters and exits, I don’t think that will cause colors to split, i.e. no chromatic aberration.
This should be a great technology for camera phones and whatnot, that are already focused at infinity. More aperature with the same size optical element is a good thing IMO.
Also, it seems this is the sort of optical technology that is needed to make use of the smaller higher density CCD’s that are starting to appear. Five megapixel phones, with optics that can exploit it anyone?
Still, nothing beats a big hunk of glass in your objective lens.
2,
That also assumes that each mirror/crystal interface is perfectly constructed and in alignment with every other interface, and the lens is mounted exactly parallel to the sensor inside the camera. I’m not saying that it isn’t doable, I’m interested in how much it will cost to make good lenses using this technique.
3,
Frankly, a far better tech for reducing the size of optics in camera phones and other space-constrained applications is liquid lens technology, which is not only cheap but is also zoomable and robust. A company called Varioptic is currently developing systems using this technology.
Fixed focus?
Interesting if they could be sold as tele-photo adapters/filters – the way wide angle, telephoto, and macro adapters are?
Slapping a thin, 5x [10x?] filter on the front of my existing lens, when I would be focusing at infinity anyway, would be nice.
But, the diagram on the linked story shows the lens mounted directly in front of the sensor.
Without the hole in the central mirror, will this design still have the “ring” effect in out-of-focus highlights?
If it could reduce costs it would be nice. The last time I priced a quality 300 mm prime lens it was $8k.
#4,
I read your links. I think they have different applications really. I have dabbled in optics, I make telescopes. For me, a large objective is always a better solution. Larger optic means more light and faster exposure. Better color, and sharpness. With a 5 megapixel or greater ccd, just use a digital zoom. I think with that technique you get good shots up to 8x digital zoom. Even better telephoto shots with more dense or larger ccd’s. Although there are definite limits with this technique.
The technology you linked looks excellent for macro style shots. But they are concentrating on making the objective lens as small as possible. Also, it seems like the technique woud have a maximum size, depending on the fluids used. That always limits the amount of light that reaches the film/ccd. That makes longer exposures necessary.
I still think for the forseeable future professional photographers are going to go for the largest hunk of glass they can afford. These are both techniques for the point and shoot variety of cameras.
Also, I think about the fantastic success of fixed focus cameras over the last 100 years or so as enabling technology.
6,
I sincerely hope you mean zooming in on th eimage in your computer after the fact, digital zoom in a camera is a waste and a bullshit feature.
5, Considering the care that must be used in manufacture, I don’ think this will reduce any costs, it’s all about compressing the optics.
#7,
Oh you are right, framing my photograph at the camera and discarding the pixels I wont be using is a waste and bullshit. I am much better served doing that at the computer, then putting back onto the flash drive, then taking it to the developer and printing my photos out.
Woes me, What have I become, an amature photographer that takes the time to properly frame my pictures.
LOL.
What the story is NOT telling you is that the total aperture is the outer ring of forward light input. Meaning two very non-useful things: 1. The 60mm diameter limits Depth Of Field to the same effect you would have with a –new term: Ring Of Confusion. 2: As pictured on the detail page, the 60mm outer diameter has a 50mm (maybe larger) inner diameter opaque light blocking mirror in its middle. The area of the outer diameter light gathering ring is, for this example, 866 sq mm where a traditional 60mm diameter optic would have had 2827 sq mm of light gathering.
John’s concernabout chromatic aberration isn’t a big deal since mirror bounces don’t produce CA.
Several things: No zooms possible. Every picture has the out of focus detail showing up as a very bicycle-wheel like ring of confusion (fun for the first ten minutes) and as pictured, a permanent f/3.2 light flow aperture that can’t be changed, but which has the DOF of a lens out in the ozone of above f/1.0!
Where this optic makes sense is in machine vision situations where DOF is irrelevant, ring of confusion is irrelevant and space requirements are extreme.
Sometimes the Most Expensive Words In Any Language Are: “All You Have To Do Is…”
Did everybody notice that RESULTS from this image system are not included with the brilliant PR story?
My guess: Barf. Unless on very limited test subjects.
#6, I don’t know what your definition of quality is, but it is at least $7k more then necessary.
Mind you, I don’t know what size of coupling or camera you have in mind. But even the professional photographers I’ve seen have all dumped their 10 x 12s in favor of digital.
9,
Yes. Since digital zoom does nothing but sub-window the image sensor, you gain nothing in quality, and actually restrict yourself. To capture the entire scene the camera can opticall capture means that you get all the pixels the sensor can capture, allowing you to frame and re-frame the image until you are completely satisfed.
So your printer is in your camera? You don’t have a printer attached to your computer?
Why not capture all the information that your image sensor receives?
10,
You make excellent points about the aperture.
Concerning Chromatic Abberation, you are partially correct. However, since the lens is made from layered mirrors and crystal, misalignment in the layers will cause abberation.
12,
No, I use a photo printing service. SOHO inkjet printers are a huge hassle IMHO.
So you forward the images directly from your camera?
I was gonna be polite. But I haven’t had a cup of coffee yet so I get to be cranky.
From my phone, yes, I send pictures directly from my phone all the time. Have you ever used a camera phone? Nowdays they make pictures that are functional if not beautiful.
I just concluded show season. Several of the buyers in our company, spent the whole show taking pictures of the products they were buying, and sending them to their gmail account, and from email to their online Picassa albums. It is easily the slickest photograpy workflow ever.
I do a similar thing with my nice camera. However when I want to print them out I use a photo printing Kiosk. They have them pretty much everywhere now days. Also, just about every photograph developing service now accepts flash ram chips, all shapes and sizes. These are very affordable services, and they offer actual prints, rather than a photo printed on paper.
Costs way less than maintaining an inkjet printer at home. You realize that thing burns about $5 of ink every time you run the cleaning software right?
Yah, I do edit pictures on my computer. However it is easier to frame the shot on the camera, and print right from there.
Easier is not better, my friend. You can also reframe your images in those photo kiosks, so again you gain flexibility by capturing all the data your image sensor receives.
We may agree to disagree, but IMNSHO digital zoom is a cute gimmick, nothing more. To throw away data that could be used later is a waste. What if it turns out that something in the periphery of the shot was important? You can always take pixels away later but you can never add them once the image is captured.