This was amazing. Thank you for sharing. I do have a question if you do not mind. I am trying to make a homemade Raman in our college as well. I was trying the "back-scattering" scheme like yours. But found that it was really challenging to align and make sure Raman signal gets to the fiber optics. I was only successful with the 90 degree scheme. Any suggestions on alignment tips?
Crick Craze , well, that is due to the fact that the wavelength of the photons emitted upon raman scattering depends on the wavelength of the incident photons, that is, the wavelength of the raman peaks taken with a 635nm laser are different from those taken with a 532 nm laser. To solve this problem, we use a relative unit (which depends on the excitation wavelength) known as raman shift which is measured in cm^-1, so that a given raman peak has the same shift regardless on which laser you are using.
wave number is a unit of energy. By looking at those wave nmbers or Raman shifts we can come to know that there are certain vibrational modes exists in the molecular medium under consideration with the measured level spacings
Great video. I learned a lot from it. I was wondering if how could tell me how you built the connector from the fiber optic cable (#18) to the microscope objective (#17). I was interesting in creating a similar design but was concerned about how to robustly align the incident laser and the fiber optic cable. Are there commercial adapters between microscope objectives and fiber optic cables?
Awesome! Working on a couple of my own designs at the moment. I came across those repurposed/salvaged Science Surplus CCD spectrometers, too. What do you think of them? Did anything have to be done with the optical bench within them? Was any special ordering required? Also, I really like the simplistic graphs. What software are you using and where do I find it?
I am trying to understand the configuration and the function of the parts used. - Are lasers No. 3, 4, and 5 used simultaneously or they are just 3 different options? -Is the Dichroic cube splitter (No. 2) attached in the fixed position to the bottom of your box, or in a flexible position so it could be rotated to direct the beam(s) properly into to the designed optic pathway? What is the procedure that you use for its alignment? -Is there any other function that this cube performs besides directing the laser rays, or is it all it is used for? -As I understand, - please forgive me if I am not correct - the Raman effect is stronger if observed at the right angle. Is there any easy way to modify your configuration to the right angle configuration? -What is the full description of the function of the small diverging lens No. 9, what's its strength, and how do you choose its position (its center's position and the orientation)? Is it attached in the fixed position to the bottom of your box? -What is the purpose of the interference filters? How do you choose them? What is their affect? Or did you mean same as notch filters (or sometimes edge filters), the filters blocking Rayleigh spectrum, to remove the light from the laser, so only the relevant Raman bands are present? Thank you very much for sharing your design, and thank you in advance for your answers.
Hi there, - The lasers are used independently and not simultaneously. The red and the green ones are for raman spectroscopy whereas the uv one is for fluorescence spectroscopy. -The dichroic cube is fixed and it is placed in such a way that all three laser beams are focused towards the optical pathway. The alignment process was done by means of trial and error until all beams converged in a single point. -The only function of the cube is to redirect the lasers. -what do you mean by right angle? The raman signal depends a lot on the orientation of the sample so there is not a fixed optimal angle. -I don't have the detailed specifications of that component but it's just a fixed lens used to direct the laser light to a detector where the stability of the laser used can be monitored. -Yeah the interference filters are used to remove any rayleigh scattering, so that only the raman scattering reaches the detector.
Thanks for the answers that you have provided. Some more questions: -The dichroic cube: Is it glued to the bottom (if so, what glue did you use?), or you made a cut in the bottom to insert it? or something else? -Right angle in my question is the angle between the incident ray and the scattered one. Please correct me if I am wrong but I was under impression that the Raman effect is stronger if you consider the light scattered at the right angle.That is the reason for my angle question. - If I understand you correctly, you choose the diverging lens of the strength with which it spreads the laser ray from its position to the size of the detector's input screen, don't you? -How do you know that the desired laser stability is achieved. What should be the adequate reading from the detector? What do you do to adjust the system to the desired stability? -And what is the power of the lasers that you use?
Sorry for the slow reply but I've been very busy these days. -The cube is glued to the bottom using some common silicon based hot glue. -About the right angle: it all depends on the setup that you are using. Right angle might be very useful for a solution/liquid and so forth but when working with opaque solids working at a right angle is not possible. Additionally in my case I am using a lens which focuses the majority of the scattered photons towards the optical path so it's not really a problem. -Yeah that's exactly right. -Well honestly I don't use it too often (it should be used for analytical purposes, that is when you want to quantify something you need to ensure that you are working with the same laser intensity, integration time and so forth). The intensity can be followed by measuring the voltage or the current of the sensor. And it can be usually stabilized by warming up the laser for a while or by adjusting its power. -The laser is rated as a 50mw unit.
Hi I would like to know how Is powered the Science-Surplus spectrometer becaude I lose the 5 V Power supply and i don't want to male any mistakes. Thank you
Can you provide more informations about the notch filter you are using? I'm using a couple of cheap ones in series but they aren't working well. Also, how powerful is your greeen laser diode?
Hello, I like this video. I have a set of raman spectroscopy with 785 laser wavelength. But, it just work in liquid sample or some solid sample. When I choose carbon nanotube dispersed in water, no spectra detected. I use carbon in ethanol, just appear ethanol spectra. I check solid sample of carbon nanotube, I can't see typical spectra of carbon nanotube. I don't know the solution of that problem. Any solution ?
785nm laser may not be right for detecting carbon nanotubes. the 5xxnm one may be better for that. That's why some good raman spectrometers have more than one laser (wavelength).
Hi dear, good job! i do very appreciate it! anyway, I got some questions, first one: How do you exactly connect the "focusing lens" to the optic fibre: are there any rules about distances? may I put the focusing lens directly in contact with the optic fibre? or did you use the lens to focus the beam to the optic fibre? which is the rationale behind it?. Second one: how did you verify the correct focusing of the sample? I mean: how did you calibrate the distance between the sample and the focusing lens?
Hey there, The answer to both questions is by trial and error.. The focusing lens is used to focus the scattered photons on the fiber optic cable (and hence they should be at a distance so that the maximum amount of light reaches the fiber optic). About the distance to the sample, it is exactly the same principle, you should place the sample at a distance at which the laser light is perfectly focused (you can take the spectra of a reference like toluene at different distances and determine the distance at which you get maximum signal intensity)
I would think that to qualify to be regarded as a home made, it should include the spectrometer. How much do the spectrometer and the Class 4 laser cost?
Hey there, I've also made a homemade spectrometer after this project (I'll probably upload a video about that by this summer).Regarding the laser and the spectrometer I think it cost about 200-250$ in total.
I'd be very interested in your homemade design myself as well a any tips you might have. I'm planning on building the DIY Raman Pi Spectrometer as all the parts are pretty much 3D printable and most of the optics/components easily available. My only modification will be on the CCD detector side as I already have my own way of operating it manually over USB to acquire the spectral data.
That will be great, I'm also planning to design a few 3d printed spectrometers for different purposes (such as spark induced plasma spectroscopy, or even a more portable and simple raman spectrometer). However I am currently pretty busy so I'll have to wait for a month or so to keep working on that. Nevertheless, if you are interested on knowing some additional specification or something you can contact me through the email shown in the description of the channel!
This is where my project is at; hackaday.io/project/18126-dav5-v301-raman-spectrometer I've been working on it for awhile. The filter I'm going to use is a Raman Longpass Edge Filter, the only thing it cost $450.00 but the way I have mine set up it may work.
Thank you for this video! We tried to build your Raman spectrophotometer design but all we can get is a single peak around 1500 and a small peak around 600, no matter what we do. We aren't sure if this is an artifact of the laser? No amount of re-arranging gets any other result. We can get a correct peak for a blue LED light. Neither the sample holder or the notch filter have any effect on the result, you get this same peak from just after the IR filters to any point in the chain. I've sent images of the graph and device. Any tips you have would be incredibly generous and helpful.
I know I didn't build this and do not want to confuse you, but could it be that your laser is the problem? tried changing it? Also - does your notch filter trully remove the initial laser light fully (attention - which wavelengths - plural is intentional - does your laser actually produce?... how narrow is it's spectrum?...) Hm... just my two cents... have a nice day!...
This is amazing!!!! How much was the CCD detector unit? Also, what do you use the third laser for exactly? I've been trying to figure out what kind of DIY spec i should build for analytical stuff in hobby work. Like for substance id/ confirmation would raman or IR (or UV/VIS i guess) be better? and if money is a big factor would it be not much more useful to have both or is the overlap of usefulness small? Pardon my ignorance, thanks to anyone with an answer. This is great content here.
The CCD was about 150/200 $ (aprox). Two of the three lasers are for raman spectroscopy whereas the other is for fluorescence spectroscopy. About the type of spectroscopy to be used for chemical identification, it really depends on the compounds you are interested in but I would go for raman or IR as they can be used for almost any sample. Both are vibrational spectroscopies and hence provide similar info about a given compound, and probably at a diy level is easier to build a raman spectrometer.
Very nice project!! I would like to do something similar. I Just bought the detector and other parts. I would to use the spectrometer for mineral analysis.How to be sure that optical parts are correctly aligned?
Really cool! Thanks for sharing your setup. Obtaining those raman filters is a pain an therefore I wonder whether you could just attach a self-built linear ccd-based spectrometer and cover the spectrsl line where the laser wavelength is projected on the ccd with a delicate line of really black paint (black 3.0). Can't you get around the need for an unaffordable notch or edge filter this way?
absolutely phenomenal work, brilliant design and execution.
TH-cam needs people like you. Thank you for making this video.
This was amazing. Thank you for sharing. I do have a question if you do not mind. I am trying to make a homemade Raman in our college as well. I was trying the "back-scattering" scheme like yours. But found that it was really challenging to align and make sure Raman signal gets to the fiber optics. I was only successful with the 90 degree scheme. Any suggestions on alignment tips?
Wow, simple but effective. Good Job
Very nice explanation, I really appreciate it, can you kindly tell why on the x-axis there is wave number? and not the wavelength?.
Crick Craze , well, that is due to the fact that the wavelength of the photons emitted upon raman scattering depends on the wavelength of the incident photons, that is, the wavelength of the raman peaks taken with a 635nm laser are different from those taken with a 532 nm laser. To solve this problem, we use a relative unit (which depends on the excitation wavelength) known as raman shift which is measured in cm^-1, so that a given raman peak has the same shift regardless on which laser you are using.
wave number is a unit of energy. By looking at those wave nmbers or Raman shifts we can come to know that there are certain vibrational modes exists in the molecular medium under consideration with the measured level spacings
Great video. I learned a lot from it. I was wondering if how could tell me how you built the connector from the fiber optic cable (#18) to the microscope objective (#17). I was interesting in creating a similar design but was concerned about how to robustly align the incident laser and the fiber optic cable. Are there commercial adapters between microscope objectives and fiber optic cables?
Hi, I have a quick question. From the detector, what software do you use to actually see the Raman spectrum?
Hey there,
The software is SpectrumStudio
Do you think this apparatus can work efficiently for surface-enhanced Raman spectroscopy
i think so
Awesome! Working on a couple of my own designs at the moment. I came across those repurposed/salvaged Science Surplus CCD spectrometers, too. What do you think of them? Did anything have to be done with the optical bench within them? Was any special ordering required? Also, I really like the simplistic graphs. What software are you using and where do I find it?
Really interesting project! Thanks!
I am trying to understand the configuration and the function of the parts used.
- Are lasers No. 3, 4, and 5 used simultaneously or they are just 3 different options?
-Is the Dichroic cube splitter (No. 2) attached in the fixed position to the bottom of your box, or in a flexible position so it could be rotated to direct the beam(s) properly into to the designed optic pathway? What is the procedure that you use for its alignment?
-Is there any other function that this cube performs besides directing the laser rays, or is it all it is used for?
-As I understand, - please forgive me if I am not correct - the Raman effect is stronger if observed at the right angle. Is there any easy way to modify your configuration to the right angle configuration?
-What is the full description of the function of the small diverging lens No. 9, what's its strength, and how do you choose its position (its center's position and the orientation)? Is it attached in the fixed position to the bottom of your box?
-What is the purpose of the interference filters? How do you choose them? What is their affect? Or did you mean same as notch filters (or sometimes edge filters), the filters blocking Rayleigh spectrum, to remove the light from the laser, so only the relevant Raman bands are present?
Thank you very much for sharing your design, and thank you in advance for your answers.
Hi there,
- The lasers are used independently and not simultaneously. The red and the green ones are for raman spectroscopy whereas the uv one is for fluorescence spectroscopy.
-The dichroic cube is fixed and it is placed in such a way that all three laser beams are focused towards the optical pathway. The alignment process was done by means of trial and error until all beams converged in a single point.
-The only function of the cube is to redirect the lasers.
-what do you mean by right angle? The raman signal depends a lot on the orientation of the sample so there is not a fixed optimal angle.
-I don't have the detailed specifications of that component but it's just a fixed lens used to direct the laser light to a detector where the stability of the laser used can be monitored.
-Yeah the interference filters are used to remove any rayleigh scattering, so that only the raman scattering reaches the detector.
Thanks for the answers that you have provided. Some more questions:
-The dichroic cube:
Is it glued to the bottom (if so, what glue did you use?), or you made a cut in the bottom to insert it? or something else?
-Right angle in my question is the angle between the incident ray and the scattered one.
Please correct me if I am wrong but I was under impression that the Raman effect is stronger if you consider the light scattered at the right angle.That is the reason for my angle question.
- If I understand you correctly, you choose the diverging lens of the strength with which it spreads the laser ray from its position to the size of the detector's input screen, don't you?
-How do you know that the desired laser stability is achieved. What should be the adequate reading from the detector? What do you do to adjust the system to the desired stability?
-And what is the power of the lasers that you use?
Sorry for the slow reply but I've been very busy these days.
-The cube is glued to the bottom using some common silicon based hot glue.
-About the right angle: it all depends on the setup that you are using. Right angle might be very useful for a solution/liquid and so forth but when working with opaque solids working at a right angle is not possible. Additionally in my case I am using a lens which focuses the majority of the scattered photons towards the optical path so it's not really a problem.
-Yeah that's exactly right.
-Well honestly I don't use it too often (it should be used for analytical purposes, that is when you want to quantify something you need to ensure that you are working with the same laser intensity, integration time and so forth). The intensity can be followed by measuring the voltage or the current of the sensor. And it can be usually stabilized by warming up the laser for a while or by adjusting its power.
-The laser is rated as a 50mw unit.
Hi I would like to know how Is powered the Science-Surplus spectrometer becaude I lose the 5 V Power supply and i don't want to male any mistakes. Thank you
Really cool work.
your lasers look like 12v lasers. They will run on 3 volts?
Can you provide more informations about the notch filter you are using? I'm using a couple of cheap ones in series but they aren't working well. Also, how powerful is your greeen laser diode?
Thanks 4 video !📚📗📐📘✏
Where did you source filters
Hello, I like this video. I have a set of raman spectroscopy with 785 laser wavelength. But, it just work in liquid sample or some solid sample. When I choose carbon nanotube dispersed in water, no spectra detected. I use carbon in ethanol, just appear ethanol spectra. I check solid sample of carbon nanotube, I can't see typical spectra of carbon nanotube. I don't know the solution of that problem. Any solution ?
785nm laser may not be right for detecting carbon nanotubes. the 5xxnm one may be better for that. That's why some good raman spectrometers have more than one laser (wavelength).
Hi dear, good job! i do very appreciate it! anyway, I got some questions, first one: How do you exactly connect the "focusing lens" to the optic fibre: are there any rules about distances? may I put the focusing lens directly in contact with the optic fibre? or did you use the lens to focus the beam to the optic fibre? which is the rationale behind it?. Second one: how did you verify the correct focusing of the sample? I mean: how did you calibrate the distance between the sample and the focusing lens?
Hey there,
The answer to both questions is by trial and error.. The focusing lens is used to focus the scattered photons on the fiber optic cable (and hence they should be at a distance so that the maximum amount of light reaches the fiber optic). About the distance to the sample, it is exactly the same principle, you should place the sample at a distance at which the laser light is perfectly focused (you can take the spectra of a reference like toluene at different distances and determine the distance at which you get maximum signal intensity)
Chemistry 4all Chemistry 4all thanks you very much for the explanation! 👍🏻👍🏻👍🏻
Nicr. Can a poor quality filter be dangerous for this kind of detector?
MrAlebestia I have got the same question!!! If my notch filter does not filter properly the laser been, will it break the detector?
Yes it can break the detector
@@suhailab3634 ok. Could u advice any of them?
@@MrAlebestia just use a higher quality filter
I would think that to qualify to be regarded as a home made, it should include the spectrometer. How much do the spectrometer and the Class 4 laser cost?
Hey there, I've also made a homemade spectrometer after this project (I'll probably upload a video about that by this summer).Regarding the laser and the spectrometer I think it cost about 200-250$ in total.
I'd be very interested in your homemade design myself as well a any tips you might have. I'm planning on building the DIY Raman Pi Spectrometer as all the parts are pretty much 3D printable and most of the optics/components easily available. My only modification will be on the CCD detector side as I already have my own way of operating it manually over USB to acquire the spectral data.
That will be great, I'm also planning to design a few 3d printed spectrometers for different purposes (such as spark induced plasma spectroscopy, or even a more portable and simple raman spectrometer). However I am currently pretty busy so I'll have to wait for a month or so to keep working on that. Nevertheless, if you are interested on knowing some additional specification or something you can contact me through the email shown in the description of the channel!
Thanks for sharing, helped...
Good representation but Natural voice might be more suitable.
How we make ims plz
Can you please list out all components you used in this setup along with price link.
Good information.
A real voice would be better.
chem player?!?
@Riley Konecny similar taste in music also ?
Why don't you talk yourself?
It's simple, I am not an English native speaker and I want some privacy
Very nice project, thanks for sharing! Where did you find the low cost filters?
Thanks!, I bought the low cost filters on ebay (there are quite a few suppliers that sell them)
Very, very well presented and a very cleverly constructed spectrometer :)
+All Arduino All The Time! Thanks!! :)
Hey no problem, I'm working on a spectrometer myself and yours inspired me to keep moving forward :)
great! I will be glad to see your spectrometer,what are you planning to use it for?
This is where my project is at; hackaday.io/project/18126-dav5-v301-raman-spectrometer
I've been working on it for awhile. The filter I'm going to use is a Raman Longpass Edge Filter, the only thing it cost $450.00 but the way I have mine set up it may work.
Yeah, the raman filter is by far the most expensive part, however you might found a cheaper one on ebay( I bought mine for less than 150$)
I want to make one too for my homelab. What's the budget?
Nyc arrangement and whats its cost ?
Thank you for this video! We tried to build your Raman spectrophotometer design but all we can get is a single peak around 1500 and a small peak around 600, no matter what we do. We aren't sure if this is an artifact of the laser? No amount of re-arranging gets any other result. We can get a correct peak for a blue LED light. Neither the sample holder or the notch filter have any effect on the result, you get this same peak from just after the IR filters to any point in the chain. I've sent images of the graph and device. Any tips you have would be incredibly generous and helpful.
I know I didn't build this and do not want to confuse you, but could it be that your laser is the problem? tried changing it? Also - does your notch filter trully remove the initial laser light fully (attention - which wavelengths - plural is intentional - does your laser actually produce?... how narrow is it's spectrum?...) Hm... just my two cents... have a nice day!...
This is amazing!!!! How much was the CCD detector unit? Also, what do you use the third laser for exactly? I've been trying to figure out what kind of DIY spec i should build for analytical stuff in hobby work. Like for substance id/ confirmation would raman or IR (or UV/VIS i guess) be better? and if money is a big factor would it be not much more useful to have both or is the overlap of usefulness small? Pardon my ignorance, thanks to anyone with an answer. This is great content here.
The CCD was about 150/200 $ (aprox). Two of the three lasers are for raman spectroscopy whereas the other is for fluorescence spectroscopy.
About the type of spectroscopy to be used for chemical identification, it really depends on the compounds you are interested in but I would go for raman or IR as they can be used for almost any sample. Both are vibrational spectroscopies and hence provide similar info about a given compound, and probably at a diy level is easier to build a raman spectrometer.
I am going to try this one - Thanks!
Very nice project!! I would like to do something similar. I Just bought the detector and other parts. I would to use the spectrometer for mineral analysis.How to be sure that optical parts are correctly aligned?
use an independent photovoltaic multimeter combo to analyze the position and optimization of optical path at the various positions in the set-up
Really cool! Thanks for sharing your setup. Obtaining those raman filters is a pain an therefore I wonder whether you could just attach a self-built linear ccd-based spectrometer and cover the spectrsl line where the laser wavelength is projected on the ccd with a delicate line of really black paint (black 3.0). Can't you get around the need for an unaffordable notch or edge filter this way?
Can you please list all the components used or email to contact, please
i can't find the email here.