A little clarification as to why a mount such as the LDAM V10 works well with the P-73 or Oclaro 700 diode. We all know that the P-73 or Oclaro 700 are nasty diode's in the area of divergence.
Lighting Stalker noted they are also bad considering their high aspect ratio: perpendicular divergence vs. the parallel divergence....BAD....in that the aspect ratio between the two is quite high. Below is what I believe to be accurate concerning optics ( read: disclaimer due Optics Wizard in Training/Wanna'Be !! ).
First, we need to use the 2mm EFL collimation lens because the sooner we start to expand the slow axis.....the better results we get for correcting the divergence !!! By " sooner" , I mean we need to physically place the collimation lens in the optical path as close to the LD and the divergent rays as possible. The further away from the LD emitter, the greater the rays spread.
When the collimation lens is positioned only two (2) mm from the emitter......because the EFL ( Effective Focal Length) is 2mm on this lens...we capture the divergent rays and start to correct them before they spread. When we employ this method, we get the best results. The good results of this early correction are why we need to use a 2mm EFL collimation lens on these diodes.
Now...this close placement of the collimation lens to the LD has a downside...when the collimation lens is placed so close to the diode emitter....VERY small movements in the XY position of the diode itself are demanded to achieve perfect centering of the LD to the collimation lens centerline.
When poor centering of the LD to the collimation lens occur.......the far field geometry will look quite bad/distorted....with some serious aberrations. The better the centering, the cleaner the beam geometry presents at the far field.
This is why, for projector use, when using the P-73 or Oclaro 700, a typical set up uses the Adjustable Mount from Laser Show Parts. The LSP mount allows positioning of the LD relative to the collimation lens.....So does the LDAM V10
When using the LDAM V10, the X-Y movement of the LD is done with a bottom spring and three (3) additional set screws to achieve the optimal positioning. In a controlled and slow adjustable manner, the three (3) set screws move the T-cylinder up/down-left/right. The method to achieve centering is straight forward. Start by adjusting the X-Y screws so that the beam is perpendicular to the mount face, both up/down , then left/right. This adjustment is the main work.
Next, with the diode on, the collimation lens focused and no cylindricals present, observe the far field geometry. It will be a bar. Use the three (3) set screws to move the LD again, up/down-Left/right. When the bar appears to be most well defined, least bluried around the edges....then the X-Y adjustment is the best that can be achieved.
While the X-Y positioning is being set, the radial positioning is also being dialed in. Remember, the radial position of the LD needs to be such that as the beam enters the cylindrical correction lenses, the slow axis needs to be parallel to the centerline of the lenses. This parallel condition is easy to determine: When the diode is on, the collimation lens is focused and no cylindricals are present... the farfield geometry will be our old friend... the bar. This bar needs to be horizontal and parallel with your optical platform. That is all. The clamping plate applies spring loaded pressure to the back side of the component identified as the "T-Cylinder". The T-cylinder is a holder for the LD.
Again, after the optimal X-Y and radial position are achieved, the four (4) bolts on the rear face of the clamping plate are tightened down to lock the LD in the best position.
The LDAM V10 makes alignment of the P-73 / Oclaro 700 very easy !!! The bulk of the Brass construct also acts as a good heat sink for the LD.
In closing, this LD mount is fine for a lab style set-up, but alas... is not at all practical for the HH format. For the hand held format, the LSP adjustable mount must be used when working with the P-73 or the Oclaro 700 LD. This concept was demonstrated by the " Dragon's Head" build. I hope this explains a few things. Enjoy the ride !!
Note: Added pic...a select few will recognize this...R.Crumb...You ROCK !!!
