Robust and intrinsically safe laser failure detection in the electrical circuit

A light generating system comprising a solid state light source, a luminescent material element, a sensor element, and an electrical circuit, wherein:

• the solid state light source is configured to generate light source light-939, wherein the solid state light source;
• is functionally coupled to the electrical circuit;
• the luminescent material element comprises a luminescent material, wherein the luminescent material element is configured in a light receiving relationship with the solid state light source, and wherein the luminescent material is configured to convert at least part of the light source light into luminescent material light;
• and
• the sensor element comprises a sensor component, wherein the sensor element is comprised by the electrical circuit, wherein the sensor component comprises a photo-resistor, wherein the photo-resistor has a variable resistance dependent on an extend of exposure to a light selected from the group consisting of the laser light and the luminescent material light;
• and
• wherein one or more of the following applies:
• (i) the sensor component is configured to decrease resistance upon increased intensity of the light source light, wherein the sensor component is configured in parallel with the solid state light source;
• (ii) the sensor component is configured to increase resistance upon increased intensity of the light source light, wherein the sensor component is configured in series with the solid state light source;
• (iii) the sensor component is configured to decrease resistance upon increased intensity of the luminescent material light, wherein the sensor component is configured in series with the solid state light source;
• and (iv) the sensor component is configured to increase resistance upon increased intensity of the luminescent material light, wherein the sensor component is configured in parallel with the solid state light source;
• and
• wherein the light source comprises a laser light source, and wherein the electrical circuit is configured such that a change in resistance of the photoresistor leads to a lowering of the current and/or voltage to the laser light source and thus dimming down or shutting off the laser light source.