One 12 minute clip showed a girl of six being raped by a man wearing a clown mask. He later admitted buying the child-like doll to use for sex.
At Chester Crown Court, Dobson, who works as a consultant on nuclear propulsion admitted importation of an obscene item and further charges of making and possessing indecent images and was jailed for two years and eight months.
Judge Simon Berkson told him: "I had the doll shown to me and it is disgusting to think that this type of item exists and can be bought and imported all over the world.
"This was no mistake or misguided act on your part, it was meant for your perverted sexual desire towards children.
"This sexual desire was confirmed for the police when they made a search of your property and searched on the computerised equipment and found indecent still images of children and moving images. In the movies, one of which was 12 minutes long was the worst type of abuse that can happen on a child.
"You have had a very respectable job which you have held for a number of years and you have an elderly mother who relies upon you for her care and you have an 18-year-old son who I can only assume you also care for. I am told that for the importation charge this is the first sentence for the offence in England and Wales."
The court was told that the package was seized by the UK Border force on 23 September last year.
Prosecuting Peter Hussey said: "The package was sent by air from Hong Kong and it was the defendant who ordered it, and UK Border Force who intercepted it.
"There has been an ongoing operating targeting this type of package being imported into this country. The package was opened and contained a childlike sex doll which has been sent from a company run in Japan and which operates out of Hong Kong.
"There was an invoice and an advert for the doll. There is also documentation of the eBay account and the advert. The advert shows a young child posing in a sexual way."
The female doll was 105 cm in height, and a doctor gave it an age between 3 years and 8 months to 6 years and 2 months. The court heard the sender of the package had tried to hide what is was.
In mitigation Dobson's lawyer Simon Parry said the doll was "child size and not child like" but added: "He is ultimately ashamed of the situation he has got himself into and he is motivated to explore this offending behaviour and put it behind him.
"This is somebody who has had a sexual difficulty that needs to be addressed and nipping in the bud.
"He is man who since graduating from university has led a constructive hardworking life and who has contributed a lot - he is an entirely hardworking decent man. His work has benefitted the entirety of the country.
"His mother is elderly and relies on his care, his father recently died and it will impact his 18 year old son who lives with him.
"A custodial sentence will probably mean that the house will have to be sold and he will lose his current employment which would be quite catastrophic."
Dobson was also ordered to sign the Sex Offender Register for life.
After the case Det Cone Andy Kent, of Cheshire Police said: "Knowing child sex-dolls exist and are available for sex offenders to buy is sickening. For Dobson to go to great lengths to import one for his own sexual gratification shows the extent of his paraphilic interest in children.
"Dobson should serve as an example to those who think they can also commit this crime for their own selfish needs."
Border Force's Julian Doughty, Senior Manager at the Fast Parcel Joint Border Intelligence Unit, said: "The importation of dolls likes this is a new phenomena and Dobson is one of the first people sentenced in the UK in relation to such an item. Working closely with law enforcement partners, Border Force is determined to bring those involved in this type of offence to justice."
Last year authorities in Australia seized 18 shipments of child-sized sex dolls. A Japanese firm which produces more than 100 different types of child sex dolls claim they can be used to 'help paedophiles control their sexual urges' and therefore prevent crime.
