Buyers should prioritize uniformity of luminance, ensuring the light distribution across the screen has a deviation of less than 20%. The maximum brightness should reach at least 4,000 cd/m² for high-density films (like mammography) or a minimum of 2,000 cd/m² for standard X-rays. Additionally, look for PWM (Pulse Width Modulation) digital dimming technology to allow for flicker-free brightness adjustment, and ensure the color temperature is above 6,500K to provide a clear, cool white light that reduces eye fatigue for radiologists.