Several cylindrical equidistant projections were devised by R. Miller. Miller's projections have standard
parallels of 
(giving minimal overall scale distortion),
(giving minimal scale distortion over continents), and 
(Miller 1949).
Miller Equidistant Projection
See also
Cylindrical Equidistant Projection, Miller Cylindrical ProjectionExplore with Wolfram|Alpha
References
Miller, R. "An Equi-Rectangular Map Projection." Geography Rev. 34, 196-201, 1949.Miller, R. "Correction to: An Equi-Rectangular Map Projection." Geography 36, 270, 1951.Snyder, J. P. Flattening the Earth: Two Thousand Years of Map Projections. Chicago, IL: University of Chicago Press, 1993.Referenced on Wolfram|Alpha
Miller Equidistant ProjectionCite this as:
Weisstein, Eric W. "Miller Equidistant Projection." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/MillerEquidistantProjection.html