In this paper, we first analyze three major challenges in free-space blazed grating based DWDMs: pulse broadening, 1dB pass band and device packaging density. Based on these analyses, we introduce an ion-exchanged single mode fiber (SMF) compatible glass waveguide chip to solve. The origin of optical networks is linked to Wavelength Division Multiplexing (WDM) which arose to provide additional capacity on existing fibers. Current solutions are limited by trade-offs between channel spacing, crosstalk, insertion. Data bit rate, 1dB pass band and device dimensions are the key properties of dense wavelength division multiplexer (DWDM) devices. The grating has the property of diffracting light in a direction e-lated to its wavelength (Fig. Conve sely, several wavelengths O1, O2,. On coming from. The diffraction grating includes a substrate and a reflective material adjacent the substrate, wherein one or more input optical signals incident the reflective material is diffracted into one or more output optical signals over a wavelength range of at least approximately 30 nm, within which the. To address the escalating demands for data transmission, wavelength division multiplexers (WDMs) play a crucial role in optical fiber communications by significantly enhancing the data transmission capacity of optical fibers, thereby providing increased bandwidth and efficiency.