Contact lens storage/rinsing fluid is supposed to be kept cool, to prevent buildup of bacteria (or so they say). So in the morning you remove the cold lens from the cold lens storage liquid in the cold box, and rinse it with some cold lens rinsing fluid, pour a drop of cold rinsing fluid into the lens, put the cold lens into your eye, and feel the headache spreading from eyeball to the sinuses and beyond. Repeat.

Keeping the whole bottle warm is out of the question, if the instructions on the bottle are to be believed. Heating up a smaller amount of liquid beforehand is also pure guesswork, because you can't know how many times you're going to drop the lens into the sink and have to re-rinse it. Or is that just me?

I propose a Very Tiny Tankless Heater, a pass-through heater that attaches to the nozzle of the lens fluid bottle, and heats up the lens fluid on the fly. A tiny turbine would measure the flow of fluid, a tiny thermometre would measure the initial temperature, and a tiny thermostat would determine and apply the exact amount of power needed to heat the fluid to a preset temperature, say, 30° Celsius. No more freezing eyeballs.

This could also be used with other fluids that have to be stored cold but served warm, I just can't think of one at the moment.
-- Veho, Mar 31 2009

Peltier Effect http://en.wikipedia...fect#Peltier_effect
Cold But Hot [pragmatic_logistics, Mar 31 2009]

Flameless Ration Heater http://en.wikipedia...eless_ration_heater
[Spacecoyote, Apr 01 2009]

It's never been a problem for me, but they make something similar to heat shaving cream so why not contact lens solution?
-- phoenix, Mar 31 2009


Imagine a long and coiled tube attached to the tip of your lens fluid bottle. On squeezing the bottle, fluid must traverse the entire length of the tube before exiting and falling on the lens. The coiled tube can be immersed in a glass of hot water from the tap. Or you can hold the tube in your mouth or other warm orifice and warm it thus. As the lens fluid traverses the submerged tube it will warm up. Fluid stays clean in the tube. No fluid is wasted because any left in the tube will get sucked back into the bottle when finished.
-- bungston, Mar 31 2009


//other fluids that have to be stored cold but served warm//

Blood?
-- 2 fries shy of a happy meal, Apr 01 2009


Would this work? [link] (aside: I like how the diagram is labeled "rock or something" hehe).
-- Spacecoyote, Apr 01 2009


It would be great for Japanese sake. Invariably your little carafe has cooled by the last tiny cup. If I could warm a tiny 50ml cup at a time, that would be great. Or load 250ml and warm/dispense a shot at a time.
-- rossgk, Jun 10 2011



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