HOLLYWOOD — Out of a sundappled Norman house in Beverly Hills strolls Jack Lemmon, world traveler, incorporated star, and practitioner of the tender art of movie comedy. He looks absolutely spiffy in a blue denim shirt, white pants and the famous Lemmon smile.

While he smiles, he talks and walks - into the house, past some comfortable objets d'art and one very decorative wife, to a paneled den, a leather chair and a mound of cigars. He is ''between pictures,'' a phrase which has ominous overtones for some performers but, when applied to Lemmon, means he sleeps a little later in the mornings and goes to his office several times a week. His company, Jalem Productions, has just signed a contract with Columbia Pictures for six films, with Lemmon starring in four and involved in a ''creative capacity'' in at least two.

''This means,'' he says, ''that with my executive producer, Gordon Carroll, I'll be supervising the choice, the development and the treatment of the pictures, which is pretty much what I've been doing with most of my films since 'Days of Wine and Roses' anyway. This gives you the chance to fall on your own fanny. You don't stay awake nights blaming the boss, because you're the boss.

''I haven't the feeling that I'm becoming a factory - yet. Once you have gone into production, you're up to your neck with it every day, working with the writer and the director and getting into the whole physical aspect of it. Well, that's great. I want to be immersed until just before shooting, when Lemmon the actor takes over. Then I want to delegate the responsibility to other people so that I'm not at all - hopefully not one inch - detracting from the performance I should give.''

Lemmon, the world traveler, recently returned from Moscow's fourth international film festival, where ''The Great Race,'' in which he stars with Tony Curtis and Natalie Wood, won a silver prize. ''With all those message films being shown, we brought in this wild idiot farce, and some very interesting things happened. First, I think whoever chose the American entries did a brilliant job. Out of competition we showed 'The Best Man,' 'Lilies of the Field' and 'To Kill a Mockingbird.' All three jarred the Russians and they could not deny it. Aside from the fact that they were artistic films of merit, they were also unsparingly self-critical. Then we showed 'The Great Race' - $11 million of sheer fluff - as the official American entry, and somehow the combination was terribly impressive to them.

''It was pretty thrilling to sit with an audience of 2,500 Russians as they watched 'The Great Race.' They let out a guffaw at the beginning of the picture and then never stopped laughing for three hours. They heard a Russian voice translating the English dialogue, of course - but they were way ahead of it, roaring at the visual aspects.

''It's perfectly clear,'' he added, ''that the public positively loves the current cycle of broad visual comedy. Audiences want to really zoom, in a way they can't in a straight comedy of dialogue and clever lines. Maybe because of the pressures today, we want to get away from reality - there may be a touch of hysteria in all this. But the public is responding so tremendously to these films that the industry will no doubt go on making them until the cycle is exhausted. God knows, they're expensive. Comedy can't be general. It must be terribly specific and all these physical gags and chases need great rehearsal, they need props, and above all, they need time.''

Lemmon batted a hand at the cumulus of cigar smoke above his head and let down a little bathyscape of insight into the delicacies of movie comedy. ''Two things are constantly conspiring against successful comedy in films. The first, of course, if the lack of a sustained performance - the perennial actor's problem of popping into the middle of a scene without the flow, without building to it. The second trouble, the lack of an audience, is more serious.

''On a stage with a live audience, I can learn how to time my laughs, find out how the lines are going to work and change them is need be. But film is irrevocable, and without an audience you've no way to gauge. Here's a perfect example: It is almost axiomatic that people in a crowded movie house will laugh louder, longer and more often than at an early matinee, when the theater is half full. Unless people are laughing all around you, you will chuckle instead of laugh - there's a certain embarrassment under those circumstances to a guffaw, although you come out of the movie just as satisfied.

''Now when a big laugh comes with a full audience - and you don't find this out until the preview - the next four lines can be completely lost. Maybe that's a disease we all should suffer from, but sometimes the lost lines are great, and it's a pity. On the other hand, you can't afford to predict 'there'll be a big laugh there' because you have no audience to go by while you're shooting, and you may be guessing wrong. Besides, at that early matinee, the audience may chuckle for a second and then stop - and in the ensuing painful pause the pace goes right out the window.

''Billy Wilder beat the rap once with a brilliant piece of staging. In 'Some Like It Hot' he was convinced that if the audience had bought the picture all the way up to that outrageous scene where I get engaged to Joe E. Brown, they would buy that particular scene as well. You remember Tony Curtis came in and asked, 'What are you so happy about?' And I said, 'I'm engaged.' And Tony asks, 'You're what?' And I say, 'I'm engaged.' Now the audience knows it must be Joe E. Brown, because I've just been dancing with him with a rose in my teeth. Then Tony said, 'But why would a fella want to marry a fella?' And I look at him in astonishment and say, 'for security!'

''Well, these are all marvelous lines, and Billy felt it would be a shame just to have gotten a laugh only on the first one. He licked it by keeping the energy up, but taking long pauses. He had me use a pair of maracas, and every time I had a line, I'd stop dead, give the line to Tony clear, and then . . . hummmm, hmmm, hmmm,'' Lemmon leaped up humming and flailing the imaginary maracas. ''I'd start dancing around. Sure enough, each laugh was a belly laugh, but by the time I finished giving those maracas a whirl, the audience was ready for the next line.''

Wilder once described Lemmon as a man who, given a script in the afternoon, would walk up and down in bed with it all night, working on his scenes. As one of the handful of top, international stars, does he have to work quite that hard now? Wouldn't almost anything he did on screen be pretty much accepted? ''Yeah, maybe,'' Lemmon answers, ''but not by me. As a matter of fact it becomes tougher, because if you've had some great parts and some successful performances, then your problem becomes how do I either top it, or maintain that level?

''There are a hundred ways to play a scene, and I hate to settle for the first thing that comes to mind. Sure it'll get by, it'll be just dandy, but maybe there's a better way.

''The one supremely important thing is: simple. Simple, simple, simple. One point at one time - not five different things to show off your 'great technique'! That's a lot of baloney. The best performances I've ever seen in my life have been terribly simple. The more I act, and the more I hopefully learn, the less I want to do, really, if the part is good. In the upcoming Wilder picture it's going to reach a point, if we're correct, where I'm practically doing nothing. I'm just going to be a maypole and let everyone else go around me.

''It all becomes an obsession to do your best. The only thing in life that's worthwhile anyhow is not to be the best, but to do the very best you can. That's what we so seldom do, because we rarely push ourselves.''