Chinna Devarapu
@chinnadevarapu.bsky.social
Scientist and Maker. Research Fellow at Tyndall National Institute and Munster Technology University. Alumni of BHU, IITD, TU Berlin, University of Exeter.
2/3 ColorX extends this concept by repurposing fitness trackers as portable instruments capable of detecting five critical water quality parameters: nitrite, sulfate, chromium, free chlorine, and turbidity, with detection limits meeting EPA/CDC guidelines.
September 19, 2025 at 11:10 PM
2/3 ColorX extends this concept by repurposing fitness trackers as portable instruments capable of detecting five critical water quality parameters: nitrite, sulfate, chromium, free chlorine, and turbidity, with detection limits meeting EPA/CDC guidelines.
1/3 We just turned a $25 fitness tracker into a water quality monitoring device (Colorx). The results are now published. doi.org/10.3390/s251...
This is a follow-up of our ODX paper where we hacked a #fitnesstracker for bacterial growth monitoring. #WaterQuality #Sensors #odx
This is a follow-up of our ODX paper where we hacked a #fitnesstracker for bacterial growth monitoring. #WaterQuality #Sensors #odx
September 19, 2025 at 11:10 PM
1/3 We just turned a $25 fitness tracker into a water quality monitoring device (Colorx). The results are now published. doi.org/10.3390/s251...
This is a follow-up of our ODX paper where we hacked a #fitnesstracker for bacterial growth monitoring. #WaterQuality #Sensors #odx
This is a follow-up of our ODX paper where we hacked a #fitnesstracker for bacterial growth monitoring. #WaterQuality #Sensors #odx
Here is the video tutorial on how to use the #pocketspectrometer’s web interface. We had a french intern student (Gabriel Kirady) who kindly recorded this video while using the spectrometer. #OpenSource #Spectrometer #STEM #DIY #CitizenScience #Instrumentation #OpenHardware
July 5, 2025 at 11:24 AM
Here is the video tutorial on how to use the #pocketspectrometer’s web interface. We had a french intern student (Gabriel Kirady) who kindly recorded this video while using the spectrometer. #OpenSource #Spectrometer #STEM #DIY #CitizenScience #Instrumentation #OpenHardware
1/8 🧵 Update on the Pocket #Spectrometer project. Been working on upgrading from the AS7341 to AS7343 sensor. The #AS7341 worked well but only had 9 channels. The #AS7343 offers 12 channels which should be better for #colorimetric analysis. #OpenSource 💡
July 3, 2025 at 10:37 PM
1/8 🧵 Update on the Pocket #Spectrometer project. Been working on upgrading from the AS7341 to AS7343 sensor. The #AS7341 worked well but only had 9 channels. The #AS7343 offers 12 channels which should be better for #colorimetric analysis. #OpenSource 💡
Working on a web app that works with both mobiles and desktop. Follow this space for more updates on this #spectrophotometer 💡
bsky.app/profile/chin...
bsky.app/profile/chin...
April 20, 2025 at 9:59 PM
Working on a web app that works with both mobiles and desktop. Follow this space for more updates on this #spectrophotometer 💡
bsky.app/profile/chin...
bsky.app/profile/chin...
10/12: A Chinese company called Torch Bearer now sells similar devices at 3x the price (€166-€265), with above discussed upgrades with a polished software. Interestingly, the Torch Bearer team seems has no relationship with LaoKang, but their device looks candidly similar to his.
April 7, 2025 at 10:36 PM
10/12: A Chinese company called Torch Bearer now sells similar devices at 3x the price (€166-€265), with above discussed upgrades with a polished software. Interestingly, the Torch Bearer team seems has no relationship with LaoKang, but their device looks candidly similar to his.
7/12: For context: A basic professional spectrometer starts at €500-1000+. LaoKang sells his complete, working unit for €67, INCLUDING a fluorescent light for calibration! For €50 more, you get a version with an integrated cuvette holder for experiments such as fluorescence in liquids.
April 7, 2025 at 10:36 PM
7/12: For context: A basic professional spectrometer starts at €500-1000+. LaoKang sells his complete, working unit for €67, INCLUDING a fluorescent light for calibration! For €50 more, you get a version with an integrated cuvette holder for experiments such as fluorescence in liquids.
6/12: After sharing his results on Bilibili (Chinese version of Youtube), LaoKang got an overwhelming response (space.bilibili.com/349890769). So he started manufacturing them at a price point nobody thought possible.
April 7, 2025 at 10:36 PM
6/12: After sharing his results on Bilibili (Chinese version of Youtube), LaoKang got an overwhelming response (space.bilibili.com/349890769). So he started manufacturing them at a price point nobody thought possible.
3/12: The real BREAKTHROUGH is that LaoKang discovered a method to remove the Bayer filter from an camera sensor WITHOUT destroying it - something considered a "holy grail" in DIY spectroscopy (as well as Astrophotography and microscopy).
April 7, 2025 at 10:36 PM
3/12: The real BREAKTHROUGH is that LaoKang discovered a method to remove the Bayer filter from an camera sensor WITHOUT destroying it - something considered a "holy grail" in DIY spectroscopy (as well as Astrophotography and microscopy).
2/12: LaoKang took a basic design (slit + diffraction grating + camera) which was done by hundreds of hobbyists before him (for example: Public lab, Thermino Spectrometer, Gaudi labs, Thought emporium etc), but failed. But LaoKang perfected this simple design over several years.
April 7, 2025 at 10:36 PM
2/12: LaoKang took a basic design (slit + diffraction grating + camera) which was done by hundreds of hobbyists before him (for example: Public lab, Thermino Spectrometer, Gaudi labs, Thought emporium etc), but failed. But LaoKang perfected this simple design over several years.
1/14: As a DIY enthusiast who loves #spectrometers and💡, I am excited to share the story of LaoKang, a Chinese maker who turned a #DIY hobby project into a €67 #spectroscopy product. His "Garden Spectrometer" is making spectroscopy accessible by bringing a €1000+ tool for under €67 ($75)🧵👇.
April 7, 2025 at 10:36 PM
1/14: As a DIY enthusiast who loves #spectrometers and💡, I am excited to share the story of LaoKang, a Chinese maker who turned a #DIY hobby project into a €67 #spectroscopy product. His "Garden Spectrometer" is making spectroscopy accessible by bringing a €1000+ tool for under €67 ($75)🧵👇.
If you are in Europe, get this cute microscope for just €5 at #smythtoys. It has illumination, color filters, multiple lenses, and prepared slides. I'm modifying it with an #ESP-CAM and scanning stage to make automated #diy scanning microscope.
March 27, 2025 at 4:50 PM
If you are in Europe, get this cute microscope for just €5 at #smythtoys. It has illumination, color filters, multiple lenses, and prepared slides. I'm modifying it with an #ESP-CAM and scanning stage to make automated #diy scanning microscope.
5/6 Applications remain endless. For ex, we are working towards #waterquality monitoring. Initial results look very good. Performance is on par with s standard spectrophotometer. Beyond water quality monitoring, soil analysis, QC testing, etc - all are very interesting
March 9, 2025 at 11:35 PM
5/6 Applications remain endless. For ex, we are working towards #waterquality monitoring. Initial results look very good. Performance is on par with s standard spectrophotometer. Beyond water quality monitoring, soil analysis, QC testing, etc - all are very interesting
4/6 The core functionality remains unchanged - 10 spectral channels (350-1000nm), real-time display, all powered by a tiny M5StickC (~$20) with its built-in battery, screen, and buttons. Used the buttons cleverly to make great UI with just two buttons and screen powered by #MicroPython
March 9, 2025 at 11:35 PM
4/6 The core functionality remains unchanged - 10 spectral channels (350-1000nm), real-time display, all powered by a tiny M5StickC (~$20) with its built-in battery, screen, and buttons. Used the buttons cleverly to make great UI with just two buttons and screen powered by #MicroPython
3/6 The improved connection is more stable and reliable. I've redesigned the 3D-printed housing to match the new sensor form factor while keeping the ultra-compact size that made V1 special. #3DPrinting
March 9, 2025 at 11:35 PM
3/6 The improved connection is more stable and reliable. I've redesigned the 3D-printed housing to match the new sensor form factor while keeping the ultra-compact size that made V1 special. #3DPrinting
2/6 The biggest upgrade is simplified assembly with plug-and-play connections! V2 uses
@adafruit.com's #AS7341 sensor with built-in Stemma QT connector, eliminating all soldering. Connect it to the #M5StickC with a Grove-to-Stemma cable and you're ready to go! #DIY #CitizenScience
@adafruit.com's #AS7341 sensor with built-in Stemma QT connector, eliminating all soldering. Connect it to the #M5StickC with a Grove-to-Stemma cable and you're ready to go! #DIY #CitizenScience
March 9, 2025 at 11:35 PM
2/6 The biggest upgrade is simplified assembly with plug-and-play connections! V2 uses
@adafruit.com's #AS7341 sensor with built-in Stemma QT connector, eliminating all soldering. Connect it to the #M5StickC with a Grove-to-Stemma cable and you're ready to go! #DIY #CitizenScience
@adafruit.com's #AS7341 sensor with built-in Stemma QT connector, eliminating all soldering. Connect it to the #M5StickC with a Grove-to-Stemma cable and you're ready to go! #DIY #CitizenScience
(4/6) What makes this remarkable? The research team discovered these windows contain the first known natural fiber optic cables found in any living creature. See the image transmitted through these bundles, similar to endoscopes, but predating our human invention of this technology.
December 13, 2024 at 12:57 PM
(4/6) What makes this remarkable? The research team discovered these windows contain the first known natural fiber optic cables found in any living creature. See the image transmitted through these bundles, similar to endoscopes, but predating our human invention of this technology.
(3/6) The shell windows aren't simple holes. They're sophisticated structures that:
- Transmit useful light (up to 62%)
- Filter out harmful UV radiation
- Focus light with microscopic lenses
All made from regular shell material (calcium carbonate)
- Transmit useful light (up to 62%)
- Filter out harmful UV radiation
- Focus light with microscopic lenses
All made from regular shell material (calcium carbonate)
December 13, 2024 at 12:57 PM
(3/6) The shell windows aren't simple holes. They're sophisticated structures that:
- Transmit useful light (up to 62%)
- Filter out harmful UV radiation
- Focus light with microscopic lenses
All made from regular shell material (calcium carbonate)
- Transmit useful light (up to 62%)
- Filter out harmful UV radiation
- Focus light with microscopic lenses
All made from regular shell material (calcium carbonate)
(2/6) These heart-shaped shells (called heart cockles) have evolved transparent patches that solve a critical problem: how to get sunlight through a hard shell to feed symbiotic algae living inside.
December 13, 2024 at 12:57 PM
(2/6) These heart-shaped shells (called heart cockles) have evolved transparent patches that solve a critical problem: how to get sunlight through a hard shell to feed symbiotic algae living inside.
6/7
Applications of such microspectrometers are huge: lab-on-chip devices, drone sensing, satellites - anywhere you need sensitive spectral measurements in a tiny package. Look at the spectra of Venus captured even working under cloudy conditions!
Applications of such microspectrometers are huge: lab-on-chip devices, drone sensing, satellites - anywhere you need sensitive spectral measurements in a tiny package. Look at the spectra of Venus captured even working under cloudy conditions!
December 10, 2024 at 11:58 PM
6/7
Applications of such microspectrometers are huge: lab-on-chip devices, drone sensing, satellites - anywhere you need sensitive spectral measurements in a tiny package. Look at the spectra of Venus captured even working under cloudy conditions!
Applications of such microspectrometers are huge: lab-on-chip devices, drone sensing, satellites - anywhere you need sensitive spectral measurements in a tiny package. Look at the spectra of Venus captured even working under cloudy conditions!
3/7
The BIC gives high resolution by reflecting very narrow-band light (high Q resonances). But here's the smart part: they use the transmitted light for spectrum reconstruction (right image)! 💡 unlike traditional narrowband filters that use only small part of the transmitted light (left image).
The BIC gives high resolution by reflecting very narrow-band light (high Q resonances). But here's the smart part: they use the transmitted light for spectrum reconstruction (right image)! 💡 unlike traditional narrowband filters that use only small part of the transmitted light (left image).
December 10, 2024 at 11:58 PM
3/7
The BIC gives high resolution by reflecting very narrow-band light (high Q resonances). But here's the smart part: they use the transmitted light for spectrum reconstruction (right image)! 💡 unlike traditional narrowband filters that use only small part of the transmitted light (left image).
The BIC gives high resolution by reflecting very narrow-band light (high Q resonances). But here's the smart part: they use the transmitted light for spectrum reconstruction (right image)! 💡 unlike traditional narrowband filters that use only small part of the transmitted light (left image).
2/7
Here's the clever bit: Traditional spectral sensors block most incoming light (low throughput). These researchers instead used "bandstop" metasurfaces with bound states in continuum (BIC).
Here's the clever bit: Traditional spectral sensors block most incoming light (low throughput). These researchers instead used "bandstop" metasurfaces with bound states in continuum (BIC).
December 10, 2024 at 11:58 PM
2/7
Here's the clever bit: Traditional spectral sensors block most incoming light (low throughput). These researchers instead used "bandstop" metasurfaces with bound states in continuum (BIC).
Here's the clever bit: Traditional spectral sensors block most incoming light (low throughput). These researchers instead used "bandstop" metasurfaces with bound states in continuum (BIC).
1/6 🧵 I'm building what might be the smallest #opensource #spectrometer with an easy to use UI! I call it a pocket spectrometer. Combining #M5StickC (~$20) with AS7341 sensor (~$16). My goal? A complete spectrometer that is barely larger than a sample cuvette itself.
November 25, 2024 at 11:36 PM
1/6 🧵 I'm building what might be the smallest #opensource #spectrometer with an easy to use UI! I call it a pocket spectrometer. Combining #M5StickC (~$20) with AS7341 sensor (~$16). My goal? A complete spectrometer that is barely larger than a sample cuvette itself.