Photoacoustic photodetectors have been widely reported, especially working in energy calibration in photoacoustic tomography. In photoacoustic photodetectors, a point light absorber can be regarded as a pixel, so it is easy to fabricate an array detector with small-sized pixels benefiting to fast high-resolution imaging. Moreover, since the excited photoacoustic (ultrasonic) signals propagate slowly compared to electromagnetic wave, the spatial positions of adjacent absorbers are sufficiently to be distinguished from the time-domain signals. Therefore, it is expected to realize a single-wired array light detector with mull-pixels based on photoacoustic effect, solving the array detector fabrication problem and data acquisition problem caused by mull-pixels. The experimental results show that the proposed photoacoustic photodetector has the superiority to realize broad-spectral and high-resolution light measurement. We expect this detector can be widely used in different fields especially in energy calibration of photoacoustic tomography, broadening the application field of photoacoustic effect.