4 ms·

The article keeps saying "camera", but we only see the lens. How big is the sensor and cabling?

cvakang 5y ago
Yes, I had the same question. But if the lens miniaturised so does the rest. Imagine swallowing this and getting picturs of your inside of body in a smart phone.
- nine_k 5y ago
  There is a diffraction limit, which is not very small for visible light. Making a pixel grid that would resolve very tiny details may be hard. OTOH the light sensor needs not be as small. Imagine a thin optical fiber with such a lens on one end, and a large lens and large enough camera on the other end. In could immediately make a better and less invasive endoscope, e.g. for surgery.
- codingdave 5y ago
  That already exists - the term is "capsule endoscopy" if you want to find out more. But -- it is a big pill to swallow. A smaller and better camera could both make the experience better for the patient and improve results, so this is still a good step to improvements.
- brazzy 5y ago
  > But if the lens miniaturised so does the rest. Not necessarily. I recently looked into miniature cameras for self- built drones. For less than $50, you can get a package with a lens that's maybe 2-3mm across. The entire sensor+lens unit is roughly 1cm cubed. But then you need the electronics to process and store the image, and you're up to credit card size. And then you need a battery, and not a tiny one because that image processing draws quite a bit of juice.
  - euler2100 5y ago
    Mind sharing the link for such small camera sensors and lenses?
    - brazzy 5y ago
      Here's one example: https://www.aliexpress.com/item/4001057625611.html https://www.aliexpress.com/item/4001057625611.html
alted 5y ago
The full setup is in the supplementary information (available at the bottom of the main paper website [1]), Figure 7. After this small lens, there are a couple more large lenses before the final camera/sensor, apparently an AVT Proscilica GT1930C (which is not tiny---the full setup would be maybe ~200mm in length). So basically, yep, this work is just about a better tiny lens; the press article is misleading (the paper [1] is better written). I don't know enough about optics to comment on how it compares to previous work, or how small a full lens + sensor system can currently be. [1] https://doi.org/10.1038/s41467-021-26443-0 https://doi.org/10.1038/s41467-021-26443-0
- ISL 5y ago
  Fig. 7 is definitely where it's at -- I had the same question, as a camera is not just a lens, but a camera obscura[1], both the lens and the 'dark box' within which an image is formed. My impression is that their metasurface lens has approximately a 1 mm focal-length. In the diagram, the light appears to pass through an intermediate focus at that distance, which they then pick up with another optical system for control/convenience. I don't see anything that would, in principle, prevent using the metasurface lens as a component of a tiny camera. Nature has certainly evolved imaging systems that are smaller and modern sensor technology permits wavelength-scale pixels. With maximum charity, it appears that this lens/methodology might be used to yield a ~1-2 Mpx imaging system with a 1 mm f/2 optical system. The claimed advance here appears to be that the combination of their lens and processing yields higher quality imaging at these physical scales than prior work. It does indeed appear that in combination with a tiny imaging sensor, this lens could yield a camera the size of a large salt-grain. This entire field of engineering appears to be in a golden decade; it may not be too long before we start seeing metasurface optics in consumer imaging products. [1] https://www.etymonline.com/word/camera https://www.etymonline.com/word/camera

Yes, I had the same question. But if the lens miniaturised so does the rest. Imagine swallowing this and getting picturs of your inside of body in a smart phone.

nine_k 5y ago
There is a diffraction limit, which is not very small for visible light. Making a pixel grid that would resolve very tiny details may be hard. OTOH the light sensor needs not be as small. Imagine a thin optical fiber with such a lens on one end, and a large lens and large enough camera on the other end. In could immediately make a better and less invasive endoscope, e.g. for surgery.
codingdave 5y ago
That already exists - the term is "capsule endoscopy" if you want to find out more. But -- it is a big pill to swallow. A smaller and better camera could both make the experience better for the patient and improve results, so this is still a good step to improvements.
brazzy 5y ago
> But if the lens miniaturised so does the rest. Not necessarily. I recently looked into miniature cameras for self- built drones. For less than $50, you can get a package with a lens that's maybe 2-3mm across. The entire sensor+lens unit is roughly 1cm cubed. But then you need the electronics to process and store the image, and you're up to credit card size. And then you need a battery, and not a tiny one because that image processing draws quite a bit of juice.
- euler2100 5y ago
  Mind sharing the link for such small camera sensors and lenses?
  - brazzy 5y ago
    Here's one example: https://www.aliexpress.com/item/4001057625611.html https://www.aliexpress.com/item/4001057625611.html

alted 5y ago

The full setup is in the supplementary information (available at the bottom of the main paper website [1]), Figure 7. After this small lens, there are a couple more large lenses before the final camera/sensor, apparently an AVT Proscilica GT1930C (which is not tiny---the full setup would be maybe ~200mm in length). So basically, yep, this work is just about a better tiny lens; the press article is misleading (the paper [1] is better written). I don't know enough about optics to comment on how it compares to previous work, or how small a full lens + sensor system can currently be. [1] https://doi.org/10.1038/s41467-021-26443-0 https://doi.org/10.1038/s41467-021-26443-0

ISL 5y ago
Fig. 7 is definitely where it's at -- I had the same question, as a camera is not just a lens, but a camera obscura[1], both the lens and the 'dark box' within which an image is formed. My impression is that their metasurface lens has approximately a 1 mm focal-length. In the diagram, the light appears to pass through an intermediate focus at that distance, which they then pick up with another optical system for control/convenience. I don't see anything that would, in principle, prevent using the metasurface lens as a component of a tiny camera. Nature has certainly evolved imaging systems that are smaller and modern sensor technology permits wavelength-scale pixels. With maximum charity, it appears that this lens/methodology might be used to yield a ~1-2 Mpx imaging system with a 1 mm f/2 optical system. The claimed advance here appears to be that the combination of their lens and processing yields higher quality imaging at these physical scales than prior work. It does indeed appear that in combination with a tiny imaging sensor, this lens could yield a camera the size of a large salt-grain. This entire field of engineering appears to be in a golden decade; it may not be too long before we start seeing metasurface optics in consumer imaging products. [1] https://www.etymonline.com/word/camera https://www.etymonline.com/word/camera