An optical device comprising: an underlying device configured to be sensitive to input light, and to provide output light in a first spectrum based on absorbing the input light; a stacked device, formed in an active area of a single semiconductor chip, coupled in an overlapping fashion to the underlying device, the stacked device comprising: a first zone comprising: a first plurality of active elements having a first lateral size; and a first plurality of transparent regions formed in the stacked device which are transparent to the light in the first spectrum to allow light in the first spectrum to pass through from the underlying device, the first plurality of transparent regions being configured in size and shape to cause the first zone to have a first transmission efficiency for light in the first spectrum; and a second zone comprising: a second plurality of active elements having a second lateral size that is different than the first lateral size; and a second plurality of transparent regions formed in the stacked device which are transparent to the light in the first spectrum to allow light in the first spectrum to pass through from the underlying device, the second plurality of transparent regions being configured in size and shape to cause the second zone to have a second transmission efficiency for light in the first spectrum. an underlying device configured to be sensitive to input light, and to provide output light in a first spectrum based on absorbing the input light; a stacked device, formed in an active area of a single semiconductor chip, coupled in an overlapping fashion to the underlying device, the stacked device comprising: a first zone comprising: a first plurality of active elements having a first lateral size; and a first plurality of transparent regions formed in the stacked device which are transparent to the light in the first spectrum to allow light in the first spectrum to pass through from the underlying device, the first plurality of transparent regions being configured in size and shape to cause the first zone to have a first transmission efficiency for light in the first spectrum; and a second zone comprising: a second plurality of active elements having a second lateral size that is different than the first lateral size; and a second plurality of transparent regions formed in the stacked device which are transparent to the light in the first spectrum to allow light in the first spectrum to pass through from the underlying device, the second plurality of transparent regions being configured in size and shape to cause the second zone to have a second transmission efficiency for light in the first spectrum. a first zone comprising: a first plurality of active elements having a first lateral size; and a first plurality of transparent regions formed in the stacked device which are transparent to the light in the first spectrum to allow light in the first spectrum to pass through from the underlying device, the first plurality of transparent regions being configured in size and shape to cause the first zone to have a first transmission efficiency for light in the first spectrum; and a first plurality of active elements having a first lateral size; and a first plurality of transparent regions formed in the stacked device which are transparent to the light in the first spectrum to allow light in the first spectrum to pass through from the underlying device, the first plurality of transparent regions being configured in size and shape to cause the first zone to have a first transmission efficiency for light in the first spectrum; and a second zone comprising: a second plurality of active elements having a second lateral size that is different than the first lateral size; and a second plurality of transparent regions formed in the stacked device which are transparent to the light in the first spectrum to allow light in the first spectrum to pass through from the underlying device, the second plurality of transparent regions being configured in size and shape to cause the second zone to have a second transmission efficiency for light in the first spectrum. a second plurality of active elements having a second lateral size that is different than the first lateral size; and a second plurality of transparent regions formed in the stacked device which are transparent to the light in the first spectrum to allow light in the first spectrum to pass through from the underlying device, the second plurality of transparent regions being configured in size and shape to cause the second zone to have a second transmission efficiency for light in the first spectrum.