Experimental Introduction

With the rapid development of low light technology, various sensors and optoelectronic devices have emerged and are widely used in various fields such as industry, agriculture, and military. Micro light signal detection is an important means of developing high-tech and scientific research. The accuracy of micro light signal detection often plays a decisive role in the performance of products. This experiment mainly studies some characteristic parameters and signal processing methods of photomultiplier tubes in low light detection devices, so that students can have a more intuitive understanding of low light signal detection.

Experimental content

Photomultiplier tube (PMT), light sensitivity, spectral response curve, photoelectric characteristics, volt ampere characteristics.

1. Light source components:

LED tri color light source, with separate control for red, green, and blue light, and continuously adjustable light intensity.

2. Host size:

700 × 200 × 200mm, dual aperture structure, absolute dark environment, equipped with PMT and light source dual observation windows, and including circuit protection.

3. Power supply module:

High voltage module: Input voltage+14~+16V, input current 45mA, output voltage 0~-1250V, voltage control method 50k Ω potentiometer. PMT output linear current value: 100uA, input adjustment rate: 0.01%, on/off transient response rise time: 80ms, temperature coefficient: 0.03%/℃, ripple: 100mV, LED power supply current continuously adjustable.

4. Testing module:

It includes two output circuit structures: load conversion and I/V conversion. The load resistance can be adjusted in 5 levels, and the I/V conversion can be adjusted in 5 levels. The output current can be displayed, and a dark current monitoring interface is reserved.

5. Photomultiplier tube:

Side window type, spectral range: 300-650nm; Peak wavelength: 400nm, minimum effective size of cathode: 24mm × 8mm, photocathode material: double alkali, multiplier system structure: annular focusing (9 levels), anode pulse rise time: 2.2ns, dark current<50nA.

6. Experimental manual and warranty card.