Recent content by narra

term “scattering” more of a general process Is the term “scattering” more of a general process which incorporates the linear effects of reflection, refraction and diffraction?

Thanks for your comments everyone. I am quite sure the laser is broken. I sort of already knew this as the spectrum, as seen on an OSA, is weak and not particularly sharp. The problem is that if I do this measurement I could also suspect that the drive circuit is faulty and not delivering the...

Hi, I am getting some light out and I guess measuring the LI properties would allow me to clearly see if my source is lasing or not. I was wondering though if there were some typical faults that could be used to determine quickly and with some confidence if the laser had be damaged, e.g...

Hi, I was wondering if someone could tell me what the best way would be to determine if a semiconductor laser is broken using a multimeter? I have a semiconductgor laser that is still emitting but the signal appears lower than expected and it is hard to tell if it is broken internally...

Hi, I am curious to know if there any passive (or simple active) methods to convert a very coherent signal into an incoherent one? I suppose I would need to find a way to chirp the signal and a non-linear medium might be one method. Any ideas? Thanks narra

Hi Sorry, I somehow posted a question within another post. Thanks for your reply on both though. I have a few more things to ask based on your answers if you don't mind. Post 1: When you say optical gain is much higher bandwidth, do you mean in terms of gain available across and optical...

Is it possible to turn a very coherent signal into one much less Hi, I am curious to know if there any passive (or simple active) methods to convert a very coherent signal into an incoherent one? I suppose I would need to find a way to chirp the signal and a non-linear medium might be one...

What is the best way to calculate the coherence length of a laser?

Hi, I was wondering what the trade-offs were in having an optical gain (say with EDFA) compared to electrical gain (say with a PIN and transimpedance amplifier) of an optical signal. Thanks.

I work with fibre optic components and one of the specifications that I typically find for telecordia class components is a power handling capability of say 300-500mW. My first reaction is that a power that low must be an average power but then if you have a high power peak then why wouldn't...

Something that i have wondered for a long time is when an optical components power handling capability is discussed, is it the average power or peak power that is in question? Thanks.

Hi, Thanks for your reply. My understanding was that the diffraction grating just provided a means of tuning the central wavelength. I thought that perhaps the fact that the cavity was external was the key to offering ultra narrow linewidth ... although seems counter intuitive since a shorter...

Hello, How does an external cavity laser produce ultra narrow line width when it's larger cavity should reduce the free spectral range and thus introduce more longitudinal modes? Thanks.

Hi Marcusl, Thank you for your reply I still need to look into Born2wire's matrix method to understand things further. I'm not sure if it is limited to the lack of coherence, a laser source can have a coherence length of a >100m while the component is only 60mm. Although I don't fully...

Thank you both for your replies. Born2wire, you have brought a whole new level of complexity to my problem, but it's food for thought and I look forward to investigating it deeper through your matrix approach. But from what you say, it is starting to seem quite convincing as I can begin to...