An arrangement comprising a device , wherein the device comprises a luminescent material comprising element and a light transmissive element , wherein: - the device has a first device axis (A1); - the luminescent material comprising element comprises a luminescent material configured to emit luminescent material light upon irradiation with first light , wherein the luminescent material comprising element has a first length (L1) and a characteristic first dimension (D1) perpendicular to the first length (L1), wherein D1/L1<1; wherein the luminescent material comprising element is configured at a non-zero first distance (r1) from the first device axis (A1), and wherein the luminescent material comprising element at least partly surrounds the first device axis (A1); - the light transmissive element is transmissive for the first light , wherein the light transmissive element comprises an element light entrance part and an element light escape part , wherein the element light escape part and the luminescent material are radiationally coupled; wherein one or more of the following applies: (i) the first device axis (A1) intersects the light transmissive element , and (ii) the light transmissive element at least partly surrounds the first device axis (A1); and - the luminescent material comprising element is in thermal contact with one or more of (a) the light transmissive element and (b) an optional thermally conductive element , - characterised in that the light transmissive element comprises a dome-shaped body having a curved surface , wherein at least part of the curved surface comprises the element light entrance part , wherein the light transmissive element has a transmissive element axis (A2), wherein the first device axis (A1) and the transmissive element axis (A2) coincide. - the device has a first device axis (A1); - the luminescent material comprising element comprises a luminescent material configured to emit luminescent material light upon irradiation with first light , wherein the luminescent material comprising element has a first length (L1) and a characteristic first dimension (D1) perpendicular to the first length (L1), wherein D1/L1<1; wherein the luminescent material comprising element is configured at a non-zero first distance (r1) from the first device axis (A1), and wherein the luminescent material comprising element at least partly surrounds the first device axis (A1); - the light transmissive element is transmissive for the first light , wherein the light transmissive element comprises an element light entrance part and an element light escape part , wherein the element light escape part and the luminescent material are radiationally coupled; wherein one or more of the following applies: (i) the first device axis (A1) intersects the light transmissive element , and (ii) the light transmissive element at least partly surrounds the first device axis (A1); and - the luminescent material comprising element is in thermal contact with one or more of (a) the light transmissive element and (b) an optional thermally conductive element , - characterised in that the light transmissive element comprises a dome-shaped body having a curved surface , wherein at least part of the curved surface comprises the element light entrance part , wherein the light transmissive element has a transmissive element axis (A2), wherein the first device axis (A1) and the transmissive element axis (A2) coincide. <EOS>