Types of Bulbs

blue IKEA desk lamp

I was looking for a bulb size that fits my IKEA cheap lamp. I had a previous purchase before, it was an incandescent light bulb, which is very energy-inefficient, and too bright for my liking. I am worried about my eyes, which I just did my LASIK on. It turns out, there are SO many kinds of bulbs. So I had wanted to get a fluorescent bulb. But a warning sign says that this lamp takes only Type R bulbs 25W 120V, which only are available as incandescent bulbs.

http://www.elightbulbs.com/catalog_search_help_incandescent_bulb_base_types.cfm
Incandescent bulb types. Life-size type R and PAR20 (circled) are shown below. 

Why is that so? I did a search on the very informative website (above), and noticed that incandescent light bulbs are typically the conventional bulbs we see, and fluorescent ones are usually the longer kind. I reckon it's due to limitations imposed by the way fluorescence works. There are also fluorescent compact versions which I used for the bulbs in the living room (see last image below). 

This website provides an extremely good overview of bulbs. I bought also a variety of bulbs just to try them out, so that I know which to get in the future (or try more bulbs LOLX they all fit into the living room lamp anyway). Easily available from Amazon. 

BTW, the above figure for incandescent bulbs is not drawn to scale. For comparison, see image below:

Type R (left) and Type PAR20 (right)

Type R (right) and compact fluorescent spiral
(hidden within)

Type PAR20 (left) and compact fluorescent spiral