A light generating system comprising: - a plurality of k light sources configured to provide light source light , wherein k is a natural number of at least 5, wherein the light sources are configured in an array , wherein the light sources have inter-light source distances (d1); - an elongated luminescent body having a length (L), the elongated luminescent body comprising one or more side faces , the elongated luminescent body comprising a radiation input face and a radiation exit window , wherein the radiation input face is configured in a light receiving relationship with the plurality of light sources , wherein the elongated luminescent body comprises luminescent material configured to convert at least part of light source light into luminescent material light , wherein the radiation exit window has an angle (α) unequal to 0° and unequal to 180° with the radiation input face ; - a body holder structure , wherein the body holder structure comprises an elongated slit for hosting the elongated luminescent body , wherein the elongated slit comprises one or more slit side faces ; - n force applying elements configured to keep the elongated body pushed against at least one of the one or more slit side faces of the elongated slit , wherein n is a natural number selected from the range of 0.01 ∗ L/mm-0.05 ∗ L/mm, wherein the length (L) is in mm, wherein n is at least 1, characterized in that the inter-light source distance (d2 ) at the n force applying elements is larger than an average inter-light source distance (d1), - and that the n force applying elements are configured to exert a force selected from the range of 1-10 N. - a plurality of k light sources configured to provide light source light , wherein k is a natural number of at least 5, wherein the light sources are configured in an array , wherein the light sources have inter-light source distances (d1); - an elongated luminescent body having a length (L), the elongated luminescent body comprising one or more side faces , the elongated luminescent body comprising a radiation input face and a radiation exit window , wherein the radiation input face is configured in a light receiving relationship with the plurality of light sources , wherein the elongated luminescent body comprises luminescent material configured to convert at least part of light source light into luminescent material light , wherein the radiation exit window has an angle (α) unequal to 0° and unequal to 180° with the radiation input face ; - a body holder structure , wherein the body holder structure comprises an elongated slit for hosting the elongated luminescent body , wherein the elongated slit comprises one or more slit side faces ; - n force applying elements configured to keep the elongated body pushed against at least one of the one or more slit side faces of the elongated slit , wherein n is a natural number selected from the range of 0.01 ∗ L/mm-0.05 ∗ L/mm, wherein the length (L) is in mm, wherein n is at least 1, characterized in that the inter-light source distance (d2 ) at the n force applying elements is larger than an average inter-light source distance (d1), - and that the n force applying elements are configured to exert a force selected from the range of 1-10 N. <EOS>