Microphotography vol. 2: Mitsubishi 660nm Red laser diode

a few weeks ago I uploaded my first experimental steps within the microphotography area, when as a testing subject the pump IR 808nm diode used in combo with glued crystal (as to be widely seen in green laser pointers) was used. Perhaps not the most attractive background to watch compared to laser beam show, but once again curiosity and testing my patience’s limits brought me to were I stand at the moment.

I’ve literally attempted focus my attention on another not too unknown laser diode either, reaching from the realm of price-friendly red wavelength spectrum. For a faster delivery I’ve chosen Odicforce as an UK based laser company, specifically looking for an open can type of a diode for an easier depicting access. The following item fulfilled my expectations just fine:



Mitsubishi 660nm RED Laser Diode 150 200mW CW 400mW Pulse IN Antistatic BAG | eBay


Based on the original Odicforce online store source information:​

General sheet technical information

Wavelength: 660nm
Output Power CW: 150-200mW
Output Power Pulse: 400mW (Target Duty Cycle 35%)
Standard Operating Current: <250mA
Threshold Current: 85mA
Slope Efficiency: 0.97 mW/mA
Operating Voltage: 2.2-3.0V
Maximum Operating Temperature: 75
Package: TO18 Open Can (5.6mm)
Working Life: >10,000 hours at 50% Max. Power

Test Measurements by Odiforce:

170mW Optical Power @280mA
215mW Optical Power @330mA
Constant current driver max 300mA


After about one week waiting I could get my sweating hands on it, only to realise how tiny and fragile this thingy is. My very 1st "naked" laser diode handheld (in protective latex gloves). Exciting, huh? I was prepared to scratch the delicate surface of - in the most gentle photographic way I was capable of - yet another laser diode’s micro world...

The goal of this thread is to introduce a gallery that presents the testing subject in portrait positions divided in 2 stages:
1) Classic macro photo-session with appliance of 105mm f/2.8G Nikon Nikkor lens attached to Nikon D5200 DSLR body. This way I could achieve 1:1 pictures.

2) Far more time-consuming microscopic session, where Nikon D5200 with a specific DSLR microscopic adapter was attached to an eye-tube instead of the original eye-piece to simulate the look through it. Total magnification usable for the shots was 40x and 100X (microscopic objectives of 4x and 10x multiplied by 10x magnification rate of the eye-piece).

Behind both of these operations post-processing was absolutely required due to a shallow depth-of-a-field which causes severe final picture degradation and reveals very little usable visual information. Zerene Stacker as a head-line software was my guide through sticking tens to hundreds of single frame-shots per 1 full final picture (depending on chosen angle and length of the captured range). Let me state here, that every final shot was stacked (except of the true portrait/non macro pics). The deeper I proceeded, the more frames were needed, although it wasn’t always a general rule, depending on how much of the scene I wanted to have depicted. Each manual movement while turning the focusing knob on left or the right side of the microscope equals one stackshot/frame.

I must give credit again to all the members in the past (long before I joined lpf.com) who contributed in the macro field of laser diode photography. I’d like to underline three specific threads/posts closely related to my very own thread I type here.

http://laserpointerforums.com/f50/laser-diode-pictures-high-magnification-71676.html

http://laserpointerforums.com/f54/laser-diode-microscope-what-magnification-65215.html#post938394

http://laserpointerforums.com/f48/large-macro-photo-soc-loc-445nm-diode-68441.html

All of the above mentioned posts bring pretty much well very close look at the red 650-660nm type of a diode, generally speaking. The reason I’ve chosen them is the visual similarity, if not even identical appearance. Why do I want to share something that’s been shared before? Well, it’s not about my private ego really, is it (alright, perhaps a tiny bit, as tiny as the diode you notice in person for the 1st time:thinking. It’s about my “point of view” at the diode as it is.

No more tiresome words to read, let the pics do the typing.​

40x total magnification shots of the front diode section follow. Note the different colour environment caused by different light conditions and angle positions. Done on purpose and for comparison reasons​

100x total magnification shots of the chosen diode sections follow.​

Some final words to be added. I realise it’d be cool to have the precise micrometer measurements of the diode sections included, but I was clearly limited by the fact the microscopic equipment is rather a simple and basic device designed for pure observation tasks. It’d be even cooler to obtain diode depicted during the actual operation where a weak light beam is generated within safe environment. Again, no proper equipment for me there. Nothing more, nothing less. I apologise for not delivering a more complex review of the red laser diode I had a chance to explore here. Having written that, this thread remains solely as a multimedia demonstration.


:thanks: for reading & watching​