# Regulated Power Supply with High Power Factor for Hyperspectral Imaging Applications
## 3 Proposed Circuit Configuration
### Quality Assessment of the Lightning Systems for Hyperspectral Imaging  
The proposed custom power supply and two commercial power supplies were integrated into an HS setup to analyze its performance. The proposed power supply is called PPS in the experiments. The commercial power supplies (CPS) used in this experiment are an MI-150 illuminator (Dolan Jenner Industries Inc., Boxborough, MA, USA), called CPS1 in the experiments (E in Figure 8), and a TechniQuip's Model 21 DC light source (TechniQuip, Pleasanton, CA, USA), called CPS2 in the experiments (C in Figure 8). Both power supplies can generate white light with a light power of 1750 lm using a 150 W Quartz Tungsten halogen lamp, with a mean lifetime between 1000 and 10,000 h. All the power supplies (PPS, CPS1, and CPS2) were connected to two different light sources through fiber optic to measure the light in reflectance and transmittance illumination modes. The first light source is a guide light (B in Figure 8) that emits a line, and it is used in pushbroom HS cameras to capture HS images in reflectance mode. The captures were performed using a white reference tile reflecting 99% of the light (G in Figure 8). The second light source is a backlight illuminator (Dolan-Jenner QVABL fiber optic; F in Figure 8 and is used to capture HS images in transmittance mode. In this case, the HS camera captures the light directly from the backlight. Figure 8: HSI instrumentation. A: Pushbroom camera; B: guide light employed for the light reflectance experiments; C: TechniQuip’s commercial power supply (CPS1); D: proposed power supply employed (PPS); E: MI-150 commercial power supply (CPS2); F: backlight illuminator employed in the light transmission experiments; G: white reference tile employed in the light reflectance experiments. The HS camera used in this study is a pushbroom camera, which means that each frame is composed of one spatial dimension (columns) and all the spectral dimensions (rows). This HS camera is a Hyperspec VNIR A-Series (HeadWall Photonics, Fitchburg, MA, USA; A in Figure 8) and works on the spectral range from 400 to 1000 nm. In traditional pushbroom HS acquisitions, the remaining spatial dimension required to create a HS cube is obtained by spatial scanning, where either the HS camera or the sample are moved. However, in this research, we are interested in the performance of the light over time. For this reason, the third dimension of the HS cube is composed of repeated measurements of the light. In other words, the third dimension of the HS cube is a temporal profile of the evolution of the light within the experiments. This research aims to explore the influence of power sources on the quality and performance of HSI instrumentation. Illumination is a key factor in HSI instrumentation; nevertheless, the influence of the power supply in the illumination performance has not been extensively studied in the literature. To address this issue, our investigation emphasizes the importance of short-term stability, as immediate illumination performance is crucial for multiple HSI applications, especially when successive HSIs are sampled in a short time. Two distinct experimental setups were conducted to assess the efficacy of the different power supplies: reflectance and transmittance illumination. The only change in each experimental measurement was to alternate the power supply unit connected to the illumination head (whether in transmission or reflectance mode) while keeping both the HSI instrumentation and the illumination head configuration unchanged to isolate the impact of the power supply type. The power supply developed within this study (PLS) is configured to deliver an output of 150 W. Conversely, the power supplies used as benchmark (CPS1 and CPS2) were adjusted to their respective maximum allowable output power levels. For the different power supplies, the measurements were performed using the same halogen lamp and illumination head.