3V LED Pulse Circuit
Not boost converter nor Op Amps, but low RdsOn CMOS Logic Relaxation Oscillator with a Schmitt Trigger.

but DON'T use a HC14 , it has too high an output ESR @3V and use 10M 0.1uF for 0.5s ramp ( due to 1/3Vdd= Va=1V not ~60%=T)
BOM

Single inverter CMOS SMD  https://www.fairchildsemi.com/datasheets/NC/NC7SV14.pdf
&lt; 3.3V  &gt;20mA

10MOhm feedback R and &gt;0.1 uF low leakage cap to ground on input for &lt;1Hz

Panasonic 2032 Coil cell Lithium 300mAh 3.0V
http://ca.mouser.com/ProductDetail/Panasonic-Battery/BR-2032-F2N/?qs=sGAEpiMZZMtEV04R3uo8FkXjBlacmoUJ1qGWoW%2fSZ8M%3d

Series Cap to IR LED Pair 330uF low ESR,45 mOhms, 4V Tanatlaum
http://ca.mouser.com/ProductDetail/AVX/TPSD337K004R0045/?qs=sGAEpiMZZMtZ1n0r9vR22dzXiwOw%252bhWCeYXuhE8EaaA%3d

2032 Coin cell holder

AWG30 magnet wire for hookup (burn thru insulation with solder)

IR LEDs ( your choice ) mine is Vishay Sharp types 5mm.

Kapton tape for insulation.


This should last a few days.