REFLECTING MIRROR, SURFACE LIGHT-EMITTING LASER, SOLID-STATE LASER, OPTICAL ACOUSTIC DEVICE, AND IMAGE FORMING APPARATUS

摘要

PROBLEM TO BE SOLVED: To achieve high reflectance and a wide reflection band in a reflecting mirror having a GaN layer arranged between an AlGaN layer and an InGaN layer.SOLUTION: There is provided a reflection mirror that has first layers 1 including AlGaN, second layers 2 including InGaN, and third layers 3 including GaN on a substrate 10 including GaN, where the first layers 1 and the second layers 2 are alternately laminated; the third layer 3 is arranged at least at a part between the first layer 1 and the second layer 2; x and y satisfy the specific formula; the first layer 1 has the thickness smaller than the thickness of the second layer 2; and when the center wavelength of a reflection band of the reflecting mirror is λ, the second layer 2 has an optical thickness of λ/8 or more and 3λ/8 or less.