Fig. 1. (a) Structural diagram of three-element addressable array. The inset shows the top view of a fabricated three-element addressable array. (b) Cross-sectional sketch of a 16-element VCSEL array. The inset shows the top view of a fabricated 16-element array. (c) Cross-sectional sketch of a 61-element VCSEL array. The inset shows the top view of a fabricated 61-element array.

Fig. 2. Output power and voltage characteristics for injection currents supplied to the left element only, the top element only, and the right element only. The array elements are defined as the left element, the top element, and the right element, as shown in the inset.

Fig. 3. Near-field profiles of each element of the three-element array measured below and above the threshold.

Fig. 4. Schematic of experimental setup and positions used for measurement of the optical distribution, the near-field profiles, the far-field patterns, and the spectra to be measured.

Fig. 5. Top: optical field distributions in the active region of the array when measured for various Itop values while Ileft and Iright were fixed at 3.8 mA and 0 mA, respectively. Bottom: spectra and far-field patterns measured under various bias conditions.

Fig. 6. Calculated index profiles through the left and top array elements (across the A–A′ direction shown in the inset) under various bias conditions.

Fig. 7. Output power of the array versus injection current Iright when Ileft and Itop were fixed at 3.8 mA and 3.2 mA, respectively. The insets show the near-field (NF) and far-field (FF) profiles that were measured at different currents for the right element.

Fig. 8. (a) Top: measured near-fields of implant-defined 16-element in-phase coupled VCSEL arrays under various bias currents below threshold. Middle: measured near-fields of these arrays under various bias currents above threshold. Bottom: corresponding far-fields of these arrays measured at various currents above threshold. (b) P–I curve of 16-element VCSEL array under continuous wave conditions. (c) Spectra of the array measured under different current conditions.

Fig. 9. Measured P–I characteristics of a 61-element in-phase coupled VCSEL array. The insets shown on the right are the near-fields, far-fields, and spectra that were measured at different currents.

Fig. 10. Measured P–I characteristics of a 61-element out-of-phase coupled VCSEL array. The insets shown on the right are the near-fields, far-fields, and spectra that were measured at different currents.

Fig. 11. Calculated current density (unit: A·m−2) distribution of 61-element VCSEL array with metal grids.