what does glass diodes do different than black plastic package?

Some glass diodes are germanium, why are they glass?

what is the advantage of glass and what is the disadvantage?

 

it's just a different packaging choice, the pros and cons are mostly mechanical

for example, in a vacuum system, glass diodes are preferred because they do not outgass like a plastic would

on the other hand, glass is much more fragile

 

So glass last longer?

How about cold and hot temps? does glass last better and longer?

 

I wouldn't say either lasts longer
either could be designed to last centuries of constant operation

there is no "better and longer" for all circumstances, it's a matter of how they are mechanically engineered for the expected environments (in the case of your question, temperature)

 

So glass packages are better with temperature?

 

Glass is also essentially perfectly hermetic whereas plastic is not, so glass is preferred in high humidity or wet environments. That's why plastic packages are seldom used in Military or other critical environments.

 

Glass diodes are sensitive to ambient light. Black plastic diodes are not.

Ken

 

Glass is also essentially perfectly hermetic whereas plastic is not

What do you mean by hermetic? the advantage is?

 

What do you mean by hermetic? the advantage is?

A hermetic seal is a fluid-tight glass-to-metal bond. Gasses and liquids cannot penetrate the diode and contaminate it.

Ken

 

What do you mean by hermetic? the advantage is?

Look up the meaning of hermetic if you don't know.

 

Look up the meaning of hermetic if you don't know.

What do you mean, "look up the meaning"?

 

What do you mean, "look up the meaning"?

Let me Google that for you.

 

What do you mean, "look up the meaning"?

You've never heard of Google or a language dictionary? Are you related to Dexter?