Is 532nm the Optimum Wavelength for Atmospheric Particle Tracking?

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In summary: The author states that optimum wavelength to track atmospheric particles determined system design; thus, lidar instead of radar. Average pulse energy refers to multiple pulses over time with attention to beam expansion and divergence at intended target ranges.The average pulse energy is the total energy in each pulse. The author defines pulse energy as the total of the energy in each pulse.
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pyroartist
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Looking for the definition of a term.
In reading scientific papers on atmospheric pulsed Lidars there is often a table that includes system information such as the type of laser, the power in uJ or mJ and the rep rate. Examples of the power would be usually somewhere between 50 uJ and 30 mJ. Rep rates are between 10 and 10,000 pulses a second. Here is just one of many such articles:
http://www.scielo.org.za/scielo.php?pid=S0038-23532009000600018&script=sci_arttext
My question: Is the power listed the value for each pulse or is it the total of the pulses in one second? This has never been made clear in any article so it must be commonly known among Lidar engineers.
If you have a link for this answer I would like to see it please.
Thanks.
 
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If the author does it they way most laser people do, then it's the energy in each pulse. It's just too confusing to talk about the energy in 10, 100, or 1000 pulses, then you would have to also say how many pulses in your definition. Everyone with any sense will default to 1 pulse.

BTW: I didn't read your link, so I may have misunderstood something.
 
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pyroartist said:
Examples of the power would be usually somewhere between 50 uJ and 30 mJ. Rep rates are between 10 and 10,000 pulses a second.
The unit of energy is the joule. The rate of energy flow is power in watts.
A pulse energy of 1mJ repeated 100 times per second would be 100mJ/sec = 100mW.
The power of one pulse is less meaningful. It would be the pulse energy divided by the pulse duration.
 
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From the article:

1608740596249.png


The author states that optimum wavelength to track atmospheric particles determined system design; thus, lidar instead of radar. Average pulse energy refers to multiple pulses over time with attention to beam expansion and divergence at intended target ranges.

Consider also the maximum unambiguous range of pulsed transmit/receive systems. This allows one to optimize PRF/PRT (pulse repetition frequency and its reciprocal, pulse repetition time) depending on required range and vice-versa. The linked calculator applies to radar, lidar and some acoustic models.
 
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Klystron said:
optimum wavelength to track atmospheric particles
LOL, ok. What an unusual coincidence that it landed on/near 532nm, which is the very cheapest (i.e. easiest) wavelength to generate in high power visible lasers, and one that Continuum is good at doing. Thank god they didn't land on 514nm where they might have needed an Ar-Ion laser! Too bad it didn't land on 1064nm which is even cheaper.

OTOH, they said lidar vs. radar. Which is at least a factor of a thousand difference. So, OK, I guess it's optimum by some definition.
 
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What is pulsed lidar and how does it work?

Pulsed lidar is a remote sensing technology that uses laser pulses to measure the distance to an object or surface. It works by emitting short bursts of laser light and measuring the time it takes for the light to bounce back to the sensor. This data is then used to create a 3D representation of the object or surface.

What are the key power specifications for pulsed lidar?

The key power specifications for pulsed lidar include the pulse energy, pulse repetition rate, and average power. Pulse energy refers to the amount of energy in each laser pulse, while pulse repetition rate is the number of pulses emitted per second. Average power is the total power output over a given period of time.

How do pulsed lidar power specs affect its performance?

The power specifications of pulsed lidar can greatly impact its performance. Higher pulse energy and repetition rate can improve the range and accuracy of the sensor, while higher average power can increase the scanning speed and data collection rate.

What is the typical power range for pulsed lidar?

The typical power range for pulsed lidar is between 1-100 watts. However, this can vary depending on the specific application and the size and type of the laser used.

How do manufacturers measure and report pulsed lidar power specs?

Manufacturers typically measure and report pulsed lidar power specs using standardized units such as joules for pulse energy, hertz for pulse repetition rate, and watts for average power. They may also provide detailed specifications and performance charts for different power levels and settings.

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