Madubin hangen nesa na Aspherical
An sake fasalin siffar madubin hangen nesa na waje na musamman don duba gefe mafi kyau. Irin wannan madubin duba na baya yana hana abin da ake kira tabo kuma yana tabbatar da ganin abin hawa a gaba. Fa'idar irin wannan madubin duba baya a bayyane yake kuma yana ba da kyakkyawar ra'ayi daga abin hawa ba tare da kun juya kanku ba lokacin da kuka karkace daga layin.
