A light emitting device includes a light emitting die configured to emit light having a first dominant wavelength, and an index matched wavelength conversion structure configured to receive light emitted by the light emitting die. The index matched wavelength conversion structure includes wavelength converting particles having a first index of refraction embedded in a matrix material. The matrix material has a second index of refraction that may be substantially matched to the first index of refraction. The light emitting device may include a graded index layer having an index of refraction that is continuously graded from a first index of refraction in a first region of the graded index layer near the light emitting die to a second index of refraction in the graded index layer away from the light emitting die.