By "normal light" they mean normal white light illumination, most pre-existing sub-diffraction resolution techniques use illumination of fluorescent dyes which require illumination by a specific light wavelength and do can only detect the stained structures.
It is a matter of simplicity of optics, damage to the sample and contrast. Visible light optics are very advanced (i.e. glass lenses), but it starts to get difficult as you head towards shorter wavelenths. X rays, especially high energy (short wavelength) ones, are extremely hard to focus. Short wavelengths of light also damage biological samples (imagine UV and sunburn). A key requirement for generating an image is high contrast, use of very short wavelength light/electrons requires heavy metal staining to get good contrast, not exactly ideal for looking at a living cell.
Microscopes are directly limited by diffraction. And near field generally means lambda distances. A normal microscope objective lens is far further away from the sample than this!
My Tattoo came with two pieces of demo software preinstalled. They are great fun; they ran 5 times, ran out of demo time and now sit clogging up my memory...
It was very rare for a student to be using a laptop in a lecture or class during my undergrad (at Cambridge in the UK, finished last year). The vast majority of students own a laptop, you would just not consider bringing it to your lectures!
As far as I know this is universal across the UK.
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By "normal light" they mean normal white light illumination, most pre-existing sub-diffraction resolution techniques use illumination of fluorescent dyes which require illumination by a specific light wavelength and do can only detect the stained structures.
It is a matter of simplicity of optics, damage to the sample and contrast. Visible light optics are very advanced (i.e. glass lenses), but it starts to get difficult as you head towards shorter wavelenths. X rays, especially high energy (short wavelength) ones, are extremely hard to focus. Short wavelengths of light also damage biological samples (imagine UV and sunburn). A key requirement for generating an image is high contrast, use of very short wavelength light/electrons requires heavy metal staining to get good contrast, not exactly ideal for looking at a living cell.
Microscopes are directly limited by diffraction. And near field generally means lambda distances. A normal microscope objective lens is far further away from the sample than this!
My Tattoo came with two pieces of demo software preinstalled. They are great fun; they ran 5 times, ran out of demo time and now sit clogging up my memory...
It was very rare for a student to be using a laptop in a lecture or class during my undergrad (at Cambridge in the UK, finished last year). The vast majority of students own a laptop, you would just not consider bringing it to your lectures! As far as I know this is universal across the UK.