An electronic device (DS), comprising: a light source member (LP) configured to provide a first light with a first wavelength; a color conversion member (CCP) disposed on the light source member (LP) and comprising a first conversion material (QD1) adapted to convert the first wavelength of the first light into a second light with a second wavelength and a second conversion material (QD2) adapted to convert the first wavelength of the first light into a third light with a third wavelength; the first, the second, and the third wavelength being different from one another; wherein a low-refractive index layer (LRL) is disposed on the light source member (LP) and on at least one of upper and lower portions of the color conversion member (CCP), wherein the low-refractive index layer (LRL) comprises a matrix part (MX) and a plurality of hollow particles (HP) dispersed in the matrix (MX) characterized in that the hollow particles are inorganic particles (HP) and the low-refractive index layer (LRL) further comprises a plurality of void parts (VD) defined by the matrix part (MX), wherein the hollow inorganic particles (HP) have sphere shapes and a mean diameter of about 20 nm to about 200 nm, and a cross-section of each hollow inorganic particle (HP) has a circular shape, and wherein the first light is a blue light, the first conversion material (QD1) is a first quantum dot that converts the blue light into a green light, and the second conversion material (QD2) is a second quantum dot that converts the blue light into a red light, the first and the second quantum dot have a particle having a size of a nano scale and a full width of half maximum FWHM of an emission wavelength spectrum of about 45 nm or less. a light source member (LP) configured to provide a first light with a first wavelength; a color conversion member (CCP) disposed on the light source member (LP) and comprising a first conversion material (QD1) adapted to convert the first wavelength of the first light into a second light with a second wavelength and a second conversion material (QD2) adapted to convert the first wavelength of the first light into a third light with a third wavelength; the first, the second, and the third wavelength being different from one another; wherein a low-refractive index layer (LRL) is disposed on the light source member (LP) and on at least one of upper and lower portions of the color conversion member (CCP), wherein the low-refractive index layer (LRL) comprises a matrix part (MX) and a plurality of hollow particles (HP) dispersed in the matrix (MX) characterized in that the hollow particles are inorganic particles (HP) and the low-refractive index layer (LRL) further comprises a plurality of void parts (VD) defined by the matrix part (MX), wherein the hollow inorganic particles (HP) have sphere shapes and a mean diameter of about 20 nm to about 200 nm, and a cross-section of each hollow inorganic particle (HP) has a circular shape, and wherein the first light is a blue light, the first conversion material (QD1) is a first quantum dot that converts the blue light into a green light, and the second conversion material (QD2) is a second quantum dot that converts the blue light into a red light, the first and the second quantum dot have a particle having a size of a nano scale and a full width of half maximum FWHM of an emission wavelength spectrum of about 45 nm or less. <EOS>