Simple homemade Raman spectrometer / microscope

[carmatic]

TL;DR

Please help me design and find the right parts for my Raman microscope.

Hello everyone, I am attempting to make a Raman spectrometer which can double as a microscope. It uses a 532nm laser for excitation, an infinity-corrected microscope objective to collimate the light, a 200 lines/mm diffraction grating, and a confocal lens pinhole setup. A 5 megapixel camera , with the lens focused at infinity for receiving collimated light, is at 90 degrees relative to the direction at which the light hits the diffraction grating.
The diffraction grating splits the wavelengths below 532nm towards the camera when the face normal is around 80 degrees relative to the incoming light, and reflects a full microscopic image when rotated to 45 degrees.

The focal point from the laser light appears as a bright dot in the middle of the microscopic image.
The confocal lens pinhole setup, in the inset, is used to isolate the light from this bright dot to be diffracted and separated into the individual wavelengths. It can be moved aside to allow the full image from the microscope objective to pass when a microscope image is desired.

Can someone verify that this is a correct design and the parts are okay?
Thanks in advance

Here are the numbered parts:
1. Arducam Raspberry Pi 5mp camera https://www.amazon.com/dp/B012ETE75I/?tag=pfamazon01-20

2. 1200 Grooves, 12.7mm Square, 1000nm Ruled Diffraction Grating https://www.edmundoptics.com/p/1200-grooves-127mm-square-1000nm-ruled-diffraction-grating/5257/

3. 12.5mm Diameter 45°, Green Dichroic Filter https://www.edmundoptics.com/p/1200-grooves-127mm-square-1000nm-ruled-diffraction-grating/5257/

4. 12.7mm Dia. x 19.1mm FL, VIS 0° Coated, Achromatic Lens https://www.edmundoptics.com/p/127mm-dia-x-191mm-fl-vis-0deg-coated-achromatic-lens/10223/

5. 532nm, 12.5mm Diameter, OD 4.0 Notch Filter https://www.edmundoptics.com/p/532nm-125mm-diameter-od-4-notch-filter/21647/

6. Olympus PLN 4X Objective https://www.edmundoptics.com/p/olympus-pln-4x-objective/29221/

Laser https://www.amazon.com/dp/B018Z7ZLYY/?tag=pfamazon01-20

 

[carmatic]

I have access to a laser cutter and I have also built a provisional enclosure for the parts. I already own most of the parts except the confocal pinhole setup. I tried it out with a plastic bottle; The main plastic bottle body gives a broad response from green to red, while the bottle cap has a weak red signal in addition to the green Rayleigh scattering.

The camera seems to be picking up some invisible radiation which shows up as purple in the images, I would assume that it is unwanted infrared light from the laser?

 

[dlgoff]

Summary:: ... and find the right parts

Photonics Spectra may be a good place to find parts.
Here's their web site: https://www.photonics.com/; Check out their buyers guide.

 

[carmatic]

Correction, the link for item 3 , the green dichroic filter, is https://www.edmundoptics.com/p/125mm-diameter-45deg-green-dichroic-filter/7285/