Did I?
I am trying to make this low-cost.
A DIN 60X objective (diverging) costs around £130, a 60X collimating objective costs around £1,300.
Ideally I would like to create a epi-illumination set-up, but it looks like I will only be able to achieve trans-illumination because of the...
The problem I have is that I am trying to produce a low-cost fluorescence system and as such I am trying to filter the excitation wavelength (488nm +/-10nm) from the emission wavelength of 515nm.
With such a tight band between exciatation and emission, the best filters, including the dichroic...
Hi,
Is there a particular type of optical filter which is suited for use with diverging light? Most of the filters which I have encountered; dichroic, interference ... are suited to collimated light.
I have an application where I would like to long pass filter a diverging beam of light...
OK, so I have my diverging source. One biconvex lens will collimate the diverging beam, another biconvex lens will take the collimated beam and focus it at its focal length?
Two asides:
1) If my assumption above is correct, then between the two biconvex lens (where the beam is collimated)...
Do you mean to use a collimating lens?
My light source has a divergence angle of 5 deg, and I wanted to use a biconvex lens to act as a condenser to focus the beam to a point.
I was hoping not to have to use a collimating lens due to the low cost nature of the application.
Regards,
Tom
Hi,
If I have a diverging light source, incident on a biconvex lens used for focusing the beam to a point.
How would one calculate the optimum distance between the lens and the beam source for optimum focusing? May question arises because I would expect the lens to be more efficient at...
Hi,
I have some small channels filled with a fluid (say water with a conductivity in the order 5.5e-6 S m^-1). I am simulating the various flows etc using COMSOL. In the simulation I have created a potential on one of the boundaries, say 2V and have grounded another of the boundaries. All the...
Hi,
I am not sure if this is the right place to post a COMSOL question. If not I apologise, could you point me to the right place.
I have a 3D geometry in COMSOL shape like a "T" where I want to model flow using navier stokes and a chemical diffusion using convection and diffusion. Both...
Hi,
I have designed and built my own impedance spectroscopy instrument, using a lock-in amplifier approach, with a reference signal. I know the basic theory behind impedance and impedance spectroscopy. However, I would like some thoughts on experimental set-up.
I have a reference source...
Hi ATGM,
Thank you for this useful link. I am submitting my thesis on Thursday, but I am continuing to work in this area.
I found that Maxwell 2D software provided a very good approximation for coplanar geometries, plus it also produced electric field intensity plots; which helped in the...
Thanks Guys,
Some very interesting points raised by marcusl, especially regarding:
I have been using the Boundary Element Method for parallel plates in 3D and that has produced some good results compared to my experimental results. I was thinking that it probably would not work for...
Hi,
Why does C=Eo*Er*(A/d) only work for a parallel plate geometry? Which part of it dictates its exclusivity to a parallel geomtery?
Why can't I make the plate separation, d the distance between two adjacent (coplanar) plates and it give me the capacitance of that geometry?
Any links...
Hi,
Does anyone know an equation/approximation/model or other to estimate the capacitance between two coplanar (adjacent) plates?
I know that for parallel plates: C = E0*Er*(A/d). I also know that the capacitance decrease as the plates move from a parallel to a coplanar geometry as the...
Hi,
Could someone help me understand why charge accumulates at the edges / corners of items - such as our fingers... but more importantly on the edges / corners of plate capacitors!
Thank you in advance.
Regards
Tom