## 1 Introduction  
The development of high-energy ultrafast fiber lasers has attracted much interest owing to their inherent advantages including compactness, high stability, high-power capability, and turnkey operation. Motivated by demands from several key industrial and scientific applications, such as material processing, nonlinear microscopy, and high-field physics, impressive progress has been achieved in the past few decades due to both the development of novel fiber technologies and the discovery and control of novel mode-locking regimes, especially the exploitation of dissipative soliton regimes, in which significant energy scaling is achieved [1; 2; 3; 4]. Erbium-doped fiber lasers are now a widespread technology in many applications such as free-space telecommunications, range finding, remote sensing, and medical procedures. Another category of applications of interest concerns the generation of ultrashort pulses outside the wavelength window covered by rare-earth-based fiber lasers, in particular for applications in biophotonics [5; 6] and sensing [7], where low-noise pulsesare required. In this frame, efficient fiber laser systems based on frequency conversion processes, e.g., four-wave mixing (FWM), have been developed, enabling wavelength tunability over several hundreds of nanometers [8]. To date, the best performances in terms of noise are obtained with synchronously pumped fiber optical parametric oscillators (FOPOs). Their combination with spectral or dispersion-based filters allowed broad tunability and high energies in the 0.7-1.3 \(\upmu\)m wavelength range [5; 6; 9]. The extension of this technology in the range around 1.7 \(\upmu\)m, which is attractive due to the enhanced penetration depth in nonlinear bio-imaging [10], and is now a challenge attracting strong attention from the scientific community [11; 12; 13; 14; 15; 16; 17]. Different fiber-based solutions have then been proposed, from systems relying on soliton self-frequency shift [10; 18; 19] to a FOPO driven by a master-oscillator-power-amplifier (MOPA) [12; 20; 21], to name a few. The noise characteristics of these systems and/or the use of bulky and fragile components, such as rod-type fibers, are however limiting factors for real-world applications in nonlinear imaging or ultrafast instrumentation. There is thus an identified need not only for FOPO systems emitting around 1.7 \(\upmu\)m but also for efficient and versatile fiberized pump sources featuring at the same time relatively high energies, good noise characteristics, and the possibility to directly generate highly-chirped pulses as, in this case, dispersive tuning within the FOPO cavity can offer a supplementary degree of freedom for the FOPO's tunability. A common method developed to initially obtain high-energy ultrashort pulses from Er-doped fiber lasers relies on the principle of a chirped pulse oscillator (CPO), which takes advantage of the concept of a dissipative soliton laser [22; 23; 24]. In this configuration, stable mode-locked operation can be achieved using strong mode-locking mechanisms, which could include either components with high-nonlinearity such as semiconductor saturable absorber mirrors (SESAMs) [25] or nonlinear polarization evolution (NPE). The pulses are then highly chirped due to the high-normal group dispersion delay (GDD) nature of such oscillators and could be linearly de-chirped to produce ultrashort pulses with high peak powers. In this article, we first review the various developments of the all-normal-dispersion fiber lasers in the last few years. We then report and review the design and realization of a large normal dispersion mode-locked erbium-doped fiber laser emitting dissipative solitons at 1560 nm and use numerical simulations to highlight the specific self-similar dynamics occurring within the cavity.