An inner lens for a vehicle lamp, comprising: a light transmission part configured to receive at least a portion of a light beam output from a light source and output a transmission light beam, wherein the transmission light beam comprises a first transmission light beam and a second transmission light beam; a light distribution formation part configured to generate, based on the transmission light beam output from the light transmission part, a first light beam having a light distribution pattern, and externally output the first light beam, wherein the light distribution pattern defines a pattern light beam having light properties that satisfy regulations to provide information to an outside person, wherein the light distribution formation part includes: a first light distribution formation portion configured to receive the first transmission light beam and externally output a first light distribution pattern, and wherein the first transmission light beam is diffused in the first light distribution output area, through which the first transmission light beam is output, within the first light distribution formation portion; and an image formation part configured to generate, based on the transmission light beam output from the light transmission part, a second light beam having an image pattern, and externally output the second light beam, wherein the image pattern defines a pattern light beam providing aesthetics to the outside person, wherein the image formation part includes a light guide (310; 320) extending in a guide direction offset from an output direction of the first light distribution formation portion and configured to receive and guide the second transmission light beam in the guide direction, and wherein the first light distribution formation portion includes an extension area extending between the first light distribution output area and the light guide (310; 320) in the output direction of the first light distribution formation portion, wherein the extension area is corrosion-treated to scatter at least a portion of the first transmission light beam passing through the light transmission part. a light transmission part configured to receive at least a portion of a light beam output from a light source and output a transmission light beam, wherein the transmission light beam comprises a first transmission light beam and a second transmission light beam; a light distribution formation part configured to generate, based on the transmission light beam output from the light transmission part, a first light beam having a light distribution pattern, and externally output the first light beam, wherein the light distribution pattern defines a pattern light beam having light properties that satisfy regulations to provide information to an outside person, wherein the light distribution formation part includes: a first light distribution formation portion configured to receive the first transmission light beam and externally output a first light distribution pattern, and wherein the first transmission light beam is diffused in the first light distribution output area, through which the first transmission light beam is output, within the first light distribution formation portion; and an image formation part configured to generate, based on the transmission light beam output from the light transmission part, a second light beam having an image pattern, and externally output the second light beam, wherein the image pattern defines a pattern light beam providing aesthetics to the outside person, wherein the image formation part includes a light guide (310; 320) extending in a guide direction offset from an output direction of the first light distribution formation portion and configured to receive and guide the second transmission light beam in the guide direction, and wherein the first light distribution formation portion includes an extension area extending between the first light distribution output area and the light guide (310; 320) in the output direction of the first light distribution formation portion, wherein the extension area is corrosion-treated to scatter at least a portion of the first transmission light beam passing through the light transmission part.