SANWU BG20W Optics & Module Interface

 SANWU BG20W Optics

There are 4 common types of diode laser lenses:

• 3 element
• G2 (short focal) (cutting)
• G7 (similar to 3 element lens)
• G8 (Used in VG-L7x)

The G8 has these specs:

• Optimal focal range: 30-100 mm
• EFL: 8mm
• NA: .2
• Best focal range 70-75 mm
• Smallest laser beam spot: 77 x 130 microns (0.0030315 x 0.00511811")

https://endurancelasers.com/an-endurance-laser-lens-pack/

Laser Resolution

G8 Effective Resolution = 

• x = 1/.0030315 =329.9 
• y= 1/.00511811 = 195.38

This suggests that the beam is not round. The focus tests show the beam to be round?

Laser Module Interface

I need the interface specs for the 4 pin connector on the laser module.

Emailed SANWU with no response!! 

Bring out the scope!

Pin Assignments

• 12V [red]
• Gnd [black]
• TTL [wht]
• TEMP [blue]

Connector Part #

Don't know what is on what pin yet.

Is this the connector part #?: XH2.54 4 pin

From NEJE spec: 4pin PH2.0 (red: 12V, black: GND, yellow: PWM, green: temperature signal)

Module Interface Specs

Not sure if these specs apply?

NEJE Specs: 

1. The third yellow interface line is the TTL control line, the voltage range is 3.3-12V, the frequency is 0-20KHz, and it needs to be grounded.

2. The input voltage of the red and black wires is 12V3A - 12V5A, do not connect them in reverse, otherwise, the module will be damaged.

Laser Module Temperature

Temperature profiles from NEJE information

Calculating Temperature

Laser Temperature

The laser diodes temperature is displayed at the top of the VigoWorks interface so when using it calculating the temp is not necessary. I assume that the stock firmware shuts down the 12V power on over temperature?

When using Lightburn + MinGRbl this info is not available so it may be necessary to calculate temperature and interlock the laser module 12V power external to Lightburn and/or the controller.

When using a non-stock controller and software how does a laser module over-temperature condition interlock the laser power so as to prevent damage? 

Connection of NEJE module to Various Controllers

https://forum.nejetool.com/viewforum.php?f=1

References:

https://endurancelasers.com/an-endurance-laser-lens-pack/

https://en.wikipedia.org/wiki/Laser_diode

Enjoy and Please Comment,

Don