User:Pranav Rathi/Notebook/OT/2012/09/21/Fiber light for Olympus microscope

Introduction

I have invented a fiber-light system for Olympus microscope IX71. This system is compatible to Olympus power supply TH4-100. The system has 4 parts: Olympus power supply, Dolan Jenner fiber bundle, fiber-feeder and illuminator & fiber plugin adapter. Fiber plugin adapter can be directly mounted on the illuminator and the whole system can be controlled through Olympus power supply. I designed it such that it requires lest amount of machining and regular tools and components available in any optics lab.

Motivation

Why fiber-light when Olympus illuminator works fine? Following reasons why fiber-light became important:

• DNA experiments are really sensitive to temperature (thermal energy) even few degrees make a big difference.
• Microscope (optical trap) is enclosed inside an enclosure (to avoid airborne noise and currents), so within few hours temperature of the microscope wall rises almost twice due to the halogen lamp used for illumination, this heats up the entire enclosure so as the sample.
• Temperature hike may make two similar data sets which are taken some time apart different.
• Fiber light solves the problem of temperature hike by providing clean light and by removing heat production through the lamp and conduction through the microscope skin.
• With fiber light temperature inside the enclosure goes from 23.7 to 25.5 total 1.8 degree Celsius hike in comparison to halogen lamp where temperature goes from 23.7 to 49 total 25.3 degree hike over a period of 10 hours (see slide 3).

There are many good fiber-light feeder available in market by Dolan Jenner . The reason I made my own is the following:

• Olympus power supply is better designed to feed the illuminator and I wanted something which I can control through Olympus hardware. The feeder I designed can be directly controlled through Olympus power supply.
• I used Dolan Jenner fiber-feeder (fiber-lite model 3100) but it was not good enough for two reasons: For intensity I could only choose 3 settings in comparison to Olympus where I can choose any intensity, fiber-lite probably uses half rectifier because I was seeing flickers in the camera in comparison to Olympus where the intensity was smooth and constant.
• Design and construction: I designed the system such that I would have to do least amount of machining with all the components are available in normal size optics lab just as mine, take less time to make, it took me around 10 hours to make it work including troubleshooting all the bugs and costs be around $400 including my time.
• Optical trap is very sensitive to mechanical vibrations; I wanted to have something which does not have fan inside, because fan vibration can travel through the fiber bundle to the microscope and to the sample. In this design I mount an external fan mounted above the optical table so no physical contact to the fiber-feeder.

Design & Construction

Components

There are three major parts of the system.

• Filter holder & Chassis.
• Control box.
• Power supply.

The components used: