Amber Leong brought the investors of Shark Tank to tears with her story of immigrating to America, battling a life-threatening illness, and then creating a company with a $7.5 million valuation. 

"I'm just a girl from a small town in Malaysia," Leong said on Sunday night's episode. "If you have the chance and opportunity to reach for your dream, reach for your dreams." 

Leong went on ABC's business reality program seeking $750,000 in exchange for 10 percent equity in her light therapy startup Circadian Optics. Leong's Minneapolis-based company sells small and stylish lamps that mimic the color and brightness of the sun. Light therapy is designed to help users' regulate their circadian rhythm--or the body's way of telling you when to sleep and wake--which is often disrupted by late-night work schedules or excessive screen time. 

"Today, all of us slog away inside a dark office all day," Leong told the Sharks. "We're not getting enough light, and this is disrupting our body clock and making us tired and unhealthy." 

Leong experienced those exact symptoms while reportedly working long hours as a brand manager in Minnesota, so she installed a light therapy lamp at her desk. She sensed that it was working, but the device was large and obtrusive, so she set out to create one that was more subtle and appropriate for the office. 

She launched Circadian Optics in 2016 with her husband, Kin Mun Chew, and has booked $7.4 million in lifetime sales through her website, she told the Sharks when they challenged her company's $7.5 million valuation. Last year, her company sold $4 million worth of products, and she expects to book $5.6 million in sales this year. While Leong's numbers are strong, she was on Shark Tank seeking a strategic partner to help her expand into the retail market. The Sharks were enamored with Leong and, as they often do, asked about her background. 

Leong grew up poor in Malaysia and long harbored dreams of moving to America, in part because she watched too much Full House, she explained to the Sharks. She told her parents she wanted to attend college in the U.S., so they cashed out their retirement funds and borrowed money from friends for a one-way ticket and enough cash to cover her school fees for one semester. Nine months into her stay, she learned she had toxic shock syndrome--a rare and potentially fatal complication of certain bacterial infections, like Staphylococcus aureus, or staph. She was given a 50 percent chance of survival. 

Leong pulled through, went to graduate school, got a six-figure job, and sent money home to her family, she told the misty-eyed Sharks. When she built enough savings, she decided to choose "creativity over certainty" and launched her company. 

"You represent to everybody around the world who watches this show that it doesn't matter where you come from, if you put your mind to it, anything is possible," Mark Cuban told Leong. "You represent everything great about entrepreneurship and the American dream. You are freedom." 

Cuban and Lori Greiner partnered to offer Leong $800,000 for 20 percent equity split evenly between them. (The investors required that $50,000 of that outlay was to go to Leong's parents.) Kevin O'Leary and Barbara Corcoran proposed giving Leong $750,000 for 20 percent, also split evenly. 

"I know I should negotiate and be a good business partner," Leong said. "But I'm here for Lori and Mark. You have a deal."