Boost driver based on LM2621 (for laser diode)

Hi everyone,
I've been long wanting to design a general-purpose boost driver for lasers, and I decided to have a go at it. After much researching, I decided to base the design off of an LM2621. I don't have much experience with electronics, so I'm not sure whether there is something better to use or whether it will even function.

Anyway, I mainly relied on the application example from the datasheet (**broken link removed**), except I added a potentiometer for adjustable output.

The idea was to make something compact (thus, use SMD parts) that can boost the voltage from a standard Li-Ion (~3.7 V) to whatever a laser diode would need. Ideally, a constant current driver would be great, but I think what I've made is constant-voltage...
I'm not sure, though. I'm definitely lacking in understanding at this point.

Anyway, I've included the Eagle schematic and PCB images, so if anyone has tips, suggestions, spots a flaw, or knows a better design, it'd be great if you shared.

Thanks!

the device is obsolete asper National semi. I had hell of trouble searching for this for a replacement in Fujifilm camera IX-100. Only Farnel could supply.
Added, you might have trouble using for a laser diode current source. it might deliver a peak of 2.x amps as per datasheet, but not continuous. The device is too small for your need, i fear. As, anyway, other components make the design any way bigger, you may perhaps look for some other chip. i have to check whether MC34063 can work with a li-on battery.