The goal on this project is to develop an original near-infrared (NIR) optical imaging system for whole animal and deep tissue imaging at high resolution and high sensibility. Optical imaging through the NIR window (650-1000nm) provides deep penetration of light up to several centimeters into biological tissues. We have recently developed a new innovative nanoprobe based on rare earth oxide doped with neodymium exhibiting strong 800nm luminescence under 808nm illumination suggesting a new promising optical nanoprobe for in vivo bio-imaging exactly at the light absorption minimum of the NIR transparency window. However, the extremely small stock shifts (difference between excitation and emission wavelengths) renders difficult the emission and excitation separation using optical filters. However, because the emission lifetime of the neodymium emitter is long (125 μs), this separation can be done using time gated detection. Consequently, this proposal concerns the time gating approach implementing pulsed illumination from NIR diode laser and time-delayed imaging synchronized via an optical chopper. This TGL imaging system unit will comprise a high-speed optical chopper, an EMCCD camera and a pulsed fiber-coupled diode laser. TGL imaging system will be realize by synchronizing the chopper with the diode laser in antiphase, so that the detection path will only open after the laser switch off. The optical chopper will generate a TTL pulse from its reference output to trigger an in-house pulse synchronizer, which will times a fixe pulse to enable the NIR laser. The Laser light pulse illuminate the biological tissue to excite the nanoprobe. The luminescence signal will be collect by a camera lens, passes through a pinhole attach to the optical chopper and record by the EMCCD camera.