Need help with LWIR/MWIR optics - Page 1
Forum section: electronics / general

author: ArsenioDev
author_rank: Frequent Contributor
timestamp: October 13, 2018, 11:12:27 pm
content: Hey there, long time lurker of this forum.I recently acquired a bunch of the thermopile arrays that the cheapo chinese thermal cameras use and am at wits end with trying to get the cheap ZnSe and surplus aspheric Ge lens elements to work. Does anyone have a good source for cheap(i'm talking super cheap, <$100 or so) optics? I'm also looking to get some M10 optics for when I get my hands on the Sofradir Micro80 FPAs in the next month but have been coming up empty with where to get these. Any and all help is greatly appreciated.

author: Bill W
author_rank: Super Contributor
timestamp: October 14, 2018, 10:24:12 pm
content: I have 15mm f/1 and 18mm f/0.7 focal length Ge lenses available inside that price range. These were designed for older detectors around 50µm pitch 320x240 or 20mm diagonal. GBP40They are 3 element spherical designs, but have a good correction over the field when used as a complete assembly.http://www.fire-tics.co.uk/spares.htm(Hope this is not too close to advertising....)regardsBill

author: ArsenioDev
author_rank: Frequent Contributor
timestamp: October 15, 2018, 01:24:20 pm
content: Bill, got any good resolution pictures of their mounting hardware with scale objects? And how much would shipping run to the eastern USA say, VA? Cheers

author: Bill W
author_rank: Super Contributor
timestamp: October 15, 2018, 08:05:40 pm
content: I can dig out interface drawings next week. The fixture is by the 4 screws in the corners of the plates that you see in the image.Meanwhile a rough idea of scale is the 15mm diameter front element.The plate is about 80 x 40mm.regardsBill

author: Spirit532
author_rank: Frequent Contributor
timestamp: October 22, 2018, 10:42:01 pm
content: How did you get your hands on the Lapis arrays in such a small quantity?They just ignored me and a few friends that inquired.

author: Fraser
author_rank: Super Contributor
timestamp: October 22, 2018, 11:57:45 pm
content: https://www.willow.co.uk/rohm-infrared-image-sensors-from-willow.html

author: ArsenioDev
author_rank: Frequent Contributor
timestamp: October 23, 2018, 12:00:57 am
content: Issue with willow is MOQ is 200 units

author: Fraser
author_rank: Super Contributor
timestamp: October 23, 2018, 12:03:11 am
content: That is a pity.There appears to be a nice "demonstration" board. Presumably used at trade fairs.http://www.symmetron.ru/suppliers/lighting/files/lighting/components/ir-sensors/infrared-array-sensor/ML8540%20IR_sensor.pdfFraser

author: ArsenioDev
author_rank: Frequent Contributor
timestamp: October 23, 2018, 12:09:27 am
content: I got five of these, will probably keep 3 and possibly have 2 up for trades on here in custom carrier boards

author: Bill W
author_rank: Super Contributor
timestamp: October 23, 2018, 10:38:57 pm
content: The Argus 3 lens drawing.Bill

author: Fraser
author_rank: Super Contributor
timestamp: October 23, 2018, 10:49:19 pm
content: Very useful information. Thanks Bill 👍🙂Fraser

author: a59d1
author_rank: Regular Contributor
timestamp: October 23, 2018, 11:47:40 pm
content: Is this for your atmospheric sensing work?

author: ArsenioDev
author_rank: Frequent Contributor
timestamp: October 24, 2018, 12:14:39 am
content: Nope, thermal tinkering. Interesting that someone knows about my atmospheric work though lol

author: sangar
author_rank: Regular Contributor
timestamp: February 16, 2019, 05:34:48 am
content: Hi ArsenioDev,For one of my projects, I am going to use ML8540. The problem I am having is in the selection of ADC to convert analog output from ML8540. I know it gives 6fps. So, below is my calculation for the minimum ADC sample rate from ADC to be selected,1 fps = 48 x 47 pixels = 2256 pixels6 fps = 6 x 2256 pixels = 13,536 pixelsthe above means that I should select an ADC which supports minimum 13.536K samples. Am I right ? ...The second concern is ADC resolution...The spec says the measurement range is -30 to +300C and 0.5C resolution, here, what is the voltage step per 0.5 degree change ?please suggest...Thanks,Sangar