Darker more sensitive rear-view mirror

[EldRick]

I find that the dichroic rear-view mirror does not get very dark, and does not seem to be very sensitive to light levels. I often see headlights in the rear-view that seem too bright for comfort at night.

So I'm wondering if anyone has considered putting a light-gathering lense over the headlight sensor in the mirror, or some other approach to recalibrate it and make it more sensitive?

A small (maybe 8mm) half-spherical lense should collect a good bit more light for the photocell, making it more responsive to light from behind the car.

Thoughts?

[EldRick]

I ordered one of these to try out the notion: http://www.amazon.com/gp/product/B00...ilpage_o01_s00
The sensor in the rear-view mirror is only about 4mm x6mm, so this is a bit large, but if it works to focus more light on the sensor (thus making it more sensitive) I can get a smaller glass lense to replace it.

[EldRick]

Well, the $1 version acrylic lens from Amazon works quite well, even though it's a fairly lousy lens.

I stuck it on over the rear light sensor on the mirror with some stuff called ContactStick - a transparent gummy adhesive supplied between two layers of backing paper. It's easily removable from the glass, but should support the lens forever.

It's not very noticeable on the mirror at all, because your eyes are focused on things yards behind you, and it concentrates more light from behind the car directly onto the mirror sensor, thus making it more sensitive.

I find that it makes the mirror darker at night overall, and it seems to respond to headlights from behind more quickly - it seems to make the mirror more responsive to changes in the light.

I like it well enough that I've ordered a slightly smaller (10mm) real glass lens, which should work even better: http://www.edmundoptics.com/optics/o...&countryid=232

[MightyMouseTech]

I just had my windows tinted.