Transparent Ceramic Lens

A little OT, but could we see these in telesscope someday?


Casio is continuing to take the lead in this field by creating the
world's first transparent ceramic lens using Lumicera, a transparent
ceramic developed by Murata Manufacturing Co., Ltd.

Lumicera has the same light transmitting qualities as optical glass
commonly used in today's conventional camera lenses, however it has
two very important properties that caught Casio's attention. Not only
is Lumicera's refractive index (nd = 2.08) much greater than that of
optical glass (nd = 1.5 – 1.85), it also offers superior strength.
Casio has been able to create a ceramic lens with extremely high
levels of precision thanks to several factors. Under recommendations
from Casio the material itself has been refined for use in digital
camera optical lenses by endowing it with improved transmission of
short wavelength light and eliminating pores (air bubbles) that reduce
transparency. Casio has also established a complete process involving
the perfect combination of polishing material, time and pressure, and
by treating the lens with a special coating compatible with a high
refractive index.

Darren in Bakersfield

Lumicera's refractive index (nd = 2.08) much greater than that of
optical glass (nd = 1.5 – 1.85),

High index does not in itself do anyhting for an astronomical lens. What is
more important is the dispersion (variation of index with wavelength) and
partial dispersion (variation of dispersion with wavelength). These are the
things that make or break a glass for use as an objective.

If this material has an abnormal partial dispersion, then it could possibly
find use in an objective lens. It would still need to be paired with one or
more other glass types which would be needed to null out the color errors. This
would negate any advantage of superior strength or any other mechanical
properties because conventional glasses are still involved in the overall lens.


Roland Christen

This
would negate any advantage of superior strength or any other mechanical
properties because conventional glasses are still involved in the overall
lens.


Roland Christen


Question or two here..

Is the distinction here between Ceramic and Glass that Ceramics have grain
structure whereas Glass is amorphous?

Can the grain structure cause problems when trying to achieve an optimal
finish??

Just wondering...

jon

Is the distinction here between Ceramic and Glass that Ceramics have grain
structure whereas Glass is amorphous?

Can the grain structure cause problems when trying to achieve an optimal
finish??

Just wondering...

jon


What is the definition of ceramic? I think of materials (clay
materials) that are baked when I think of ceramic.

(Chris1011) wrote in message ...
Lumicera's refractive index (nd = 2.08) much greater than that of
optical glass (nd = 1.5 – 1.85),

High index does not in itself do anyhting for an astronomical lens. What is
more important is the dispersion (variation of index with wavelength) and
partial dispersion (variation of dispersion with wavelength). These are the
things that make or break a glass for use as an objective.

If this material has an abnormal partial dispersion, then it could possibly
find use in an objective lens. It would still need to be paired with one or
more other glass types which would be needed to null out the color errors. This
would negate any advantage of superior strength or any other mechanical
properties because conventional glasses are still involved in the overall lens.


Roland Christen

Agreed, although it might be useful for eyepieces.
Brian
www.caldwellphotographic.com