Jonathan Schofield left an 89-year-old victim deeply traumatised after grabbing her handbag and taking a purse containing £100.
Leeds Crown Court heard Schofield targeted residents living in bungalows on a street in Sharlston, Wakefield, on July 14 last year.
Clare Walsh, prosecuting, said Schofield knocked at the door of one of the properties and told the woman who lived there that he was looking for a ginger cat.
He left after the woman said she had not seen it.
Schofield then walked into a neighbouring property as a 76-year-old man was watching television.
Schofield went into the bedroom and began opening drawers, pretending to look for the animal.
He left empty-handed but went into another bungalow where an 89-year-old woman lived.
Schofield overpowered the woman as she tried to stop him taking her handbag.
He returned as the victim was ringing the police and threw her purse back at her.
Miss Walsh said £100 in cash had been removed from the purse.
Police were able to arrest Schofield at his home nearby on Northfield Drive as he had told one of the residents where he lived.
His trainers matched footprints found at the scene of one of the offences.
Schofield pleaded guilty to robbery and burglary.
The 89-year-old victim provided a victim statement to the court.
She described how she had worked as a nurse in war zones across the world, including Egypt, Cyprus and Kenya.
She said she was not easily frightened but the incident had left her significantly traumatised and afraid of being alone at home.
Shila Whitehead, mitigating, said Schofield had overdosed on his mental health medication at the time and had no recollection of what he had done.
Schofield was jailed for four years, nine months.
Judge Robin Mairs said: “There was no ginger cat. This was simply a ruse for you to get into other people’s homes.
“You say you have no recollection of these offences but it was clear from the commission of the offences, and the lay-out of (the street) that this was targeting of vulnerable victims.”