Multiphoton excited fluorescence (MPEF) microscopy is commonly adopted in academic studies, medical diagnoses, and industrial applications. The natural optical sectioning ability, due to the nonlinear phenomenon of multiphoton absorption via a high numerical aperture (NA) objective that focuses and generates a strong local electromagnetic field, could achieve micron/submicron spatial resolution and reconstruct three-dimensional (3D) fluorescence images for bio-structural analysis.^{1 – 4} The excitation wavelength of an ultrafast laser was chosen in the near-infrared region and low-absorption spectral window of a biological specimen so that MPEF microscopy could achieve a deep penetration depth in thick tissue. Furthermore, with the second-harmonic generation (SHG) signal that directly reveals highly polarizable molecules and non-centrosymmetric structures, the distribution of collagen and myosin could be imaged in the biospecimen without any staining needed.^{5 – 7} These advantages make MPEF and SHG suitable for in vitro and in vivo applications, such as imaging cortical vasculature or neuronal activities inside a mouse brain,^{8 – 11} high-resolution ophthalmoscope imaging for cellular retina structures,¹² muscle disease measurement,^{13 – 15} and skin disease diagnosis.¹⁶ Based on the multiphoton excitation mechanism, temporal focusing can accommodate widefield and fast MPEF imaging due to the high-throughput illumination and detection ability.^17,18 The diffraction element (e.g., a blazed grating) in temporal focusing multiphoton microscopy (TFMPM) is utilized for generating angular dispersion to separate different spectral components into different angles according to a diffraction equation. After passing through the $4\text{-}f$ imaging system, which consists of a collimating lens and objective lens, the spectral components overlap in phase to achieve temporal focusing on the focal plane of the objective. The broadened laser pulse is reconstructed to its original short pulse width to have sufficient peak power for widefield MPEF and SHG, and is less time-consuming than conventional point scanning microscopy.^{19 – 22} The axial excitation confinement (AEC) of TFMPM can achieve a few microns and depends on several system parameters, including the transform-limited pulse width, laser beam size, groove density of the diffraction grating, optical system magnification, and NA of the objective lens.^{23 – 26} With different modified system configurations, TFMPM is capable of various applications. For example, the fast 3D Brownian motion of beads can be directly tracked,^{27 – 29} and the neural activity of mouse can be analyzed with fast volumetric imaging.^{30 – 33} A heterodyne detection mechanism has been used for parallelized frequency-domain 3D fast fluorescence lifetime image measurement.³⁴ TFMPM has also been successfully combined with optical tweezers for particle and cell trapping.³⁵ Widefield multiphoton-induced ablation using high laser-pulse energy fluence in a TFMPM system has been demonstrated for chicken tendon machining, after which SHG imaging could be directly performed to view the machined tendon structure.³⁶ Furthermore, an intensity mask can be integrated with the TFMPM for fast pattern machining and axially resolved microfabrication with various materials, including photoresist,³⁷ bovine serum albumin,³⁸ graphene oxide,³⁹ and metal substrates.⁴⁰ The desired intensity pattern can also be generated from a high-resolution phase mask applied by a liquid-crystal spatial-light modulator.^{41 – 43} A phase-contrast filter can be adopted to directly transform the phase mask into an intensity pattern to probe arbitrarily neural bodies or dendrites.³⁰