2. Light the page, not your eyes
Most reading corners fail on the lamp. The usual advice from lighting guides is consistent: place the lamp slightly behind your shoulder, on the side opposite the hand you write with, so neither your head nor your hand casts a shadow on the page. Keep the bulb out of your line of sight, and set the bottom of the shade at about shoulder or eye height when you are seated.
A floor lamp with an adjustable shade makes this easy. The TMM, designed by Miguel Milá in 1961, stands 166 cm high and its parchment shade slides up and down the stem, so you can set it to your chair rather than the other way round. It comes with an 11 W LED of 1,521 lumens at 2,700 K, comfortably inside the 450–800 lumens on the page that guides recommend for reading, and the pull cord falls within reach of the chair.