A lens for distribution of light from a light emitter. The lens has thick and thin wall portions between inner and outer lens surfaces. The thick wall portion(s) are at least twice as thick as the thin wall portion(s). At least one of the inner and outer surfaces has a texturing for diffusion of emitter light passing therethrough. The lens may include at least one interface between two materials with different indices of refraction. At least one surface of the interface may have a texturing for diffusion of emitter light passing therethrough. And, a method for manufacturing of the lens by forming a lens region with a textured surface portion by injecting the thermoplastic elastomer into an injection-molding cavity defined by a shape-forming configuration with a texturing in at least one area of the cavity. The shape-forming configuration is configured to shape a thermoplastic elastomer into such thickness that the set elastomer retains the texturing.